Jump to content
Rimfire World Community
Visit Brownells Visit AR15 Builder Visit Visit Site Visit Ballistic Advantage Visit Aero Precision Visit Cabelas
Kilibreaux

Hammer Strut mod

Recommended Posts

Like many I've seen photos of GSG-5's with blown out chambers and cracked bolts, and read a lot of stories about damaged chambers.  When I first got my GSG I took note of how thin the steel is around the chamber and worried that a chamber blow out was just a matter of time...and maybe it is in an unmodified GSG.  I have carefully analyzed both how the GSG operates as well as observed the ejection port of mine being fired and videos of others and observed fire flashes that indicate high pressure is still present during ejection.  The problem is that there is very little closing force on the bolt even with the hammer down (which is where the hammer is on firing).  For a comparison take a Ruger 10/22, drop the hammer and note how much effort is required to cock the action from full closure.  Once cocked, note again how LITTLE resistance there is to the bolt opening...because with the hammer cocked the only force opposing bolt opening is the single, relatively weak recoil spring.  Clearly what keeps the bolt momentarily closed on firing with the 10/22 is the hammer spring.  In order to “blowback†the cartridge must overcome primarily that hammer spring force and leverage combined with the bolt’s resting inertia.

Now grab your GSG…drop the hammer on an empty chamber (this can be safely done by holding the bolt open about 1/8†and pulling the trigger so the firing pin does not contact the soft aluminum barrel trunion).  Now, with the hammer down, start easing the bolt open using the cocking handle and note how far open the bolt is before you feel the hammer’s resistance…about ¼â€.  Also take notice of how LITTLE resistance you feel to the bolt being withdrawn from full closure to that point where hammer spring resistance is felt.  Remember the twin recoil springs exert minimal pressure on the bolt at full closure.  This means that during firing the bolt has barely more than its resting inertia to resist opening during the cartridge’s ignition and maximum pressure phase, and so results in “early opening†with the cartridge rim and case having no external support because it is already half-way out of the chamber!  Even a low pressure cartridge can blow out a chamber or crack a bolt if high pressure is allowed to vent reward, and in the case of the .22LR, with the case coming out of the chamber too early, the stage is always set for a potential cartridge rim/case failure.  Combine this basic engineering oversight with other factors such as the overall “stiffer†nature of the GSG’s recoil springs once past that first ¼†which demands the use of hotter, higher pressure loads in order to function reliably, plus the softening of recoil and hammer springs that occurs within the first few hundred rounds fired and the early opening problem starts to magnify, hence my previous statement that maybe a chamber failure/bolt crack IS inevitable in an unmodified GSG.

Initially I thought the GSG needed a thicker chamber wall for better support but then I look around at all the other .22’s that have equally thin chamber walls with zero reports of chamber failure so that is not where the problem lies nor needs to be addressed.  Various issues put me onto the “trail†of what might be the cause of so many reports of chamber failures and cracked bolts, but the final convincing came when I watched quality video of the GSG chamber during firing and noted the amount of fire flash…I have seen this before on other .22’s (usually modified in ways that increased “back pressureâ€), and realized the bolt is simply opening TOO EARLY!  So then I considered just WHY the designers of the GSG felt the need to include a rebounding hammer in a simple .22LR system…something not found in other .22’s notably the very successful Ruger 10/22…quite possibly the “Gold Standard†of .22LR longevity and reliability.  Now that the problem was identified I knew the right answer was a modified hammer strut so the hammer ends up resting against, or very much more closely behind the bolt than as issued.  If one examines the GSG’s hammer strut they notice it has two notches, one to drive the hammer forward and the other to “index†against the hammer pin thus acting to limit hammer strut movement.  During firing the hammer is released and driven forward by the hammer spring, and during the last portion of the hammer’s throw spring pressure stops and hammer inertia alone carries the hammer to strike the firing pin, after which a small hammer return spring pulls the hammer back.  One might presume that at the instant of firing the hammer’s mass/inertia adds enough resistance to overcome the early opening situation so easily observed in a non-dynamic mode, and this is true…the hammer’s relatively tiny mass does “help†delay bolt opening but the effect is minuscule…as evidenced by the fact that the GSG has a known reputation for damaged chambers and cracked bolts.

So I proceeded to modify the hammer strut to allow it to remain in contact with the hammer’s driving pin during the full stroke and thereby add the hammer’s considerable spring resistance to the hammer’s leverage and thus create a proper delay for the bolt during the highest pressure time of the cartridge’s firing.  After being modified, now when I begin to cock my GSG with the hammer down, just as with the 10/22, the hammer/spring resistance is present immediately…all of that former ¼†of “slack†is gone.  I now have confidence that the cartridge is being held in chamber longer and the potential for a case rupture eliminated or greatly reduced.  Shooting with the modified hammer strut the GSG functions with 100% reliability, however no fire flash is ever seen at the ejection port.  Another side benefit is the interior of the receiver is CLEANER because less powder debris is being blown back into the action during firing!

While most “mods†to the GSG and any weapon are generally cosmetic an have no real impact on making the base platform more reliable or durable, modifying the hammer strut DOES make the weapon safer, and will enhance reliability, durability.  Just yesterday I fired a full 110 round drum non-stop with the modified hammer strut without a single problem.  Modifying the hammer strut is actually amazingly simple and takes very little time.  The hardest part for most would be tearing down their gun to the the strut out and then getting it all back together again.

Share this post


Link to post
Share on other sites

Your deep study of this little sub gun we all enjoy is greatly appreciated. Not only do I trust your diagnosis, but am greatly anticipating the instructions on the mod to share with entire GSG-5 community.

great job!

Share this post


Link to post
Share on other sites

Its not just the gsg, the m&p 15-22 suffers from the same problem. Looking forward to seeing the modification pics and info.

GSG and S&W should take note....as well as the other manufacturers before somebody gets seriously hurt and a lawsuit that ends up negatively affecting the entire .22 community results.

Share this post


Link to post
Share on other sites

Have you noticed that the hammer strut washer appears to be a two way washer. It has the detention on the one side which appears to accommodate the hammer spring, then it has the flat side. I wonder if that was intentional. If you use the detention side of the washer obviously the force of the spring is somewhat decreased. If you use the flat side of the washer (which is a pain to set in the trigger plate) you are getting a harder and faster slam of the hammer. I wonder if this was at least some part of the hammer strut mod?

Share this post


Link to post
Share on other sites

I think your assessment is very good, and the solution presented is a viable option. In most larger caliber semi autos, there is a disconnect that wont let the hammer fall unless the chamber is fully closed. I dont know why many of the .22 tacticals dont also have this.

This is why this problem doesnt occur with the sig522. It has a disconnect that will not allow the hammer to drop unless the bolt is fully closed.

The bolt is notched at the rear. And the disconnect must be in the notch on the bolt in order for it to fire.

Umarex and other manufacturers come from a airgun background where a disconnect isnt really necessary because they dont have to worry about case pressures during an out of battery discharge. Im seriously beginning to wonder if this oversight was just a lack of knowledge regarding proper firearm construction.

Share this post


Link to post
Share on other sites

The hammer strut mod was purely about cutting the notch that indexes against the hammer rotation pin to allow the strut to move further forward under full spring pressure.  This places the hammer with spring force right up against the back of the bolt during cartridge ignition and high pressure phase.

As for a firing pin disconnect, yes the GSG does in fact have one - actually a firing pin lock.  The problem is that when the trigger is pulled and held to the rear an entire "plate" moves forward to unlock the firing pin.  During bolt recoil the firing pin is fully unlocked all the way back and all the way forward.  Do not despair however...the firing pin return spring is strong enough to lift a house off its foundation so the potential for an inertia hit by the firing pin is somewhere between nil and impossible.  Even a jam on loading will not induce the firing pin to drive forward under inertia because of the monster return spring.

To clarify, when the GSG trigger is NOT pulled, the firing pin is in fact LOCKED.  When the GSG trigger is pulled, the firing pin unlocks and remains unlocked as long as the trigger is held to the rear.

The hammer strut mod is all about putting maximum force right up behind the bolt during the high pressure phase of cartridge ignition.  Cracked bolt housings and blown chambers are the DIRECT result of early bolt opening due to a rebounding hammer system designed purely for liability and prevention of "easy" full auto conversion and has NOTHING to do with anything beyond that.  Modding the hammer strut should be a "mandatory modification" because it eliminates the bolt pushing back half a case length during high pressure.

Share this post


Link to post
Share on other sites

I should post a photo showing the strut after modification, but I just haven't had time to get around to it.

The mod is actually quite easy and self-guiding...yep, self-guiding.

You remove the hammer and the strut.  You will note the hammer strut has two rounded depressions, one to index against a pin in the hammer to drive it forward and the other indexes to the hammer pivot pin.  Both are about the same depth.

During operation, as the hammer is cocked by action of retracting the bolt the pin inside the hammer bears against the upper notch of the strut.  When the trigger is pulled the hammer flies forward and during the last approximately 10 degrees of rotation the lower strut notch makes contact with the hammer pivot pin thus STOPPING the strut's further movement.  The hammer continues under inertia to hit the firing pin and then "bounces" back as well as being helped to retract by a small coil spring located on the left side of the hammer that acts to aid it in "rebounding."  Other than the hammer's striking inertia there is no direct pressure applied by the hammer spring during cartridge ignition.  Taking note of how other blowback .22's work, a significant portion of resistance to chamber opening is provided by the hammer and hammer spring, and the lack of it with the GSG has led to many accounts of chamber failure and cracked bolt housings...and every photo I've seen shows clearly the damaged areas are the "weak points" such as the extractor slot in the barrel and extractor slot in bolt which channels high pressure gas into the space between the bolt proper and the bolt shroud.  Also, rim failures are increased by the bolt opening too early....

Anyway, take the hammer, leave the hammer pivot pin out, insert the hammer strut so it's upper notch or depression indexes against the pin inside the hammer, then ROTATE the strut downward relative to the hammer and view where the lower strut depression appears through the hammer pivot pin hole.  You can also lay out the two pieces in the trigger shell and see the orientation with the hammer strut mounted along its line.  Basically, use a fine tip Sharpie to mark the strut then use a dremel to cut the notch deeper.  A cutting wheel deepens the notch quickly then shift to a diamond burr for fine and finishing work.  You know you're done with you connect the strut to the hammer and rotate the hammer forward and no longer see metal through the hammer pivot pin hole.

The strut is long enough so that even after deepening the pivot pin notch it still has enough extension to pass through the brass bushing that fits behind the spring and locks it into the trigger housing.

One can EASILY tell the difference between a modded strut and stock.  On a stock GSG with the hammer down, the bolt can be retracted approximately 1/4" before hammer spring resistance is met.  After being modded the bolt will start out with the hammer spring force applied.

I know, I should just post a picture but that means taking it all apart....

Share this post


Link to post
Share on other sites

That is great innovation! I am going to try it tonight. I bet that slight rearward slant the hammer has in de-cock mode is gone after the mod as well.

How many rounds do you have on the mod? One thing I did (don't know if this helps any) but I polished all of the action contact surfaces. I even went as far as polishing the sear, the lower portion of the hammer that locks into the sear. It is amazing how smooth the metal becomes; smoother than glass.

I have yet to fire mine since the polishing. 

I will keep you posted on the hammer strut mod with pics. This way you can correct me if I did something wrong. Thank you for all the info.

Share this post


Link to post
Share on other sites

I've got about 500 rounds AFTER the mod and of course everything is working perfectly - better than stock.  The mod eliminates the fear of chamber/bolt damage from early release of pressure.  After the mod the hammer does sit vertical behind the bolt.  Remember the bolt rebound spring is removed.  Also I ground the rebound notch off the hammer as well....don't need it with no rebounding hammer.

I agree with looking for ways to smooth out everything possible in the action.

Share this post


Link to post
Share on other sites

Do you mean those two long springs in the bolt carrier? Do you think it will have a negative effect if I left them in? My breech body is lock tight down pretty good.

Share this post


Link to post
Share on other sites

No, the hammer strut modification has nothing to do with the bolt group.  Those two long springs inside the "breech bolt carrier" (bolt housing) are the recoil springs and must not be removed.

In order to function safely the GSG and any blowback .22 must have spring pressure to hold the bolt shut during cartridge ignition and high chamber pressure.  When the cartridge fires pressure inside the case builds rapidly and thrusts the bullet out and down the barrel.  At the exact same time breech face thrust pushes the opposite direction.  The bullet weighs very little.  The bolt and hammer weigh many times more, plus they have the closing force of two powerful recoil springs and (in a proper blowback system) the power of the hammer spring to counteract the pushing force exerted by the cartridge case against the bolt face.  Because of the difference in mass and applied force between the bullet and operating components the bullet APPEARS to leave the barrel before the bolt opens, but what precisely happens is the bolt starts moving as the bullet starts moving, only, the bolt moves very much slower thus keeping the case in the chamber long enough for the bullet to exit the muzzle and chamber pressure to drop before the bolt has moved sufficiently to allow any meaningful escape of gas around the case and to the rear.

IF the bolt starts moving too soon during the pressure phase of firing, the case separates from the chamber wall and begins moving out thus creating an opening for high pressure gas to vent rearward.  If the bolt moves too far while pressure is high, venting gases will have enough force to damage components.  In the case of the GSG the extractor slot on the right side of the chamber is a weak spot and of course high pressure will always blow out at the weakest spot.  Another spot that "channels" high pressure gas if present is the extractor slot in the bolt which lies under the "breech bolt cover".  When gas vents into this space it can lead to a crack in the cover.

If the barrel is too short for the mass and applied force of the operating components the opposite will occur.  The bullet will speed away, chamber pressure abruptly drops and insufficient remaining force causes the bolt to open slower, fail to move back far enough, and leads to extraction issues and feed jams.

Blowback .22's differ from locked breech designs in that a locked breech means the breech face and chamber remain fully locked together until high pressure has dropped.  In a recoil operated system this means the breech and barrel bolt remain together as the entire system "recoils" and in a gas system the breech remains locked to the barrel until the bullet passes a small opening, or gas port near the muzzle that allows gas to operate an unlocking mechanism.  Locked breech systems are used when pressures being contained are higher, and because blowback systems start to become quite heavy and unwieldy when cartridge power gets beyond the mid-level pistol cartridges.  Note that blowback systems allow the bolt to SEPARATE from the chamber immediately upon firing and being moving in the opposite direction, and so it become critical that the bolt not be allowed to move to far to soon or parts damage and case rupture can occur.

Some might erroneously presume that the designers of the GSG knew what they were doing and the original design of the GSG is satisfactory for sustained operation without concern.  This is not the case.  The GSG actually uses fairly heavy reciprocating components and quite powerful recoil springs and hammer spring.  The result is the weapon demands the use of high powered loads in order to operate and this is in direct opposition to the presence of a rebounding hammer.  The hammer loses all forward spring force during the last 10 degrees of rotation (give or take) continues under inertia, hits the firing pin and "rebounds."  To aid this function, a tiny "torsion" spring is located inside the left trigger housing with an arm that pushes against a small boss on the left side of the hammer - pushes it BACK.  The hammer also has a secondary notch design so that once "rebounded" the sear will snap up and lock the hammer in this retracted position.  Sounds wonderful...but in practice it violates the fundamental requirement of a blowback system.  The hammer's mass and spring force now resides about 1/4" behind the bolt.  During high pressure the ONLY things resisting bolt opening are the recoil springs and bolt mass and at full extension the recoil springs exert very little force.  As anyone familiar with hammer-fired .22's knows, the hammer's mass, the hammer's spring force, and the hammer's LEVERAGE contribute anywhere from 1/3rd to 1/2 of the "bolt closing force."  For example:  Drop the hammer on a 10/22 and then retract the bolt.  The hammer's presence is right there from "0" to resist opening.  Drop the hammer on a P22...same thing, the hammer's spring force is right there, right AGAINST the back of the slide...there is no "slack" or "slop zone" created by the hammer rebounding.  The GSG violates this "rule" by removing 1/3 of the bolt closing force creating an imbalance in chamber pressure versus what is available to hold the breech shut...or more precisely stated DELAY the breech's opening until pressure has diminished.  Thus, the first 1/4" of travel the GSG bolt is amazingly "under supported" and routinely skirts the safe zone of operation.  Does it work?  Sure.  Does every gun experience a high pressure venting - YES, but most of the time that venting is insufficient to cause damage.

Do a search on Ruger 10/22 chamber blow outs...you'll find none.  Do a search on Walther P22 chamber blow outs...you'll find none.  Do a search on GSG chamber blow outs...you'll find some, and those are just the one's who share their experience.

I would like to point out that the GSG is loaded with operating features that provide not one WHIT toward reliability or safety, yet are present purely for limitation of liability...and they can all be removed with no decrease in function, but an INCREASE in reliability.

Bear in mind, "what you leave out can't break..." an unfortunately ignored rule in the world of modern firearms design.

The magazine disconnect...don't need it, and no combat expert would want it.  Remove and you'll never notice.

The firing pin block...totally POINTLESS and in fact only semi-functioning.  The firing pin is locked only until trigger pull, then remains fully unlocked at all times until trigger release, which means were it not for the monster firing pin rebound spring and featherweight hammer the GSG MIGHT slamfire once every blue moon.  It adds parts not needed and if removed not missed.  In FACT the GSG will function perfectly fine with NO firing pin return spring and will never slamfire...I know, I tested it, and for anyone experiencing light hits the first thing to consider is yanking that spring made to lift a house and replace it with a much lighter one or none at all....and guess what....failures to fire are gone.

The hammer rebound spring....toss it.

Hammer rebound notch....grind it off because it can ONLY serve to snag the hammer enough to cause a light hammer blow depending on sear arm movement....a person with a LIGHT trigger finger can in fact induce a hammer snag leading to failure to detonate.

Hammer strut...must be reshaped to counter the rebound feature...and in fact does not "need" the hammer pin notch at all save that the strut is intentionally a bit too short to completely remove it and ensure the hammer strut moves smoothly with the trigger group when out of the gun and hammer not cocked.  If the person assembling the gun understands the parts the hammer strut could do without the hammer pin notch completely and function 100% while ensuring the bolt stays closed as it should during high pressure.

That giant firing pin release plate on the left side....once the firing pin lock is tossed out it not only isn't needed but it creates drag on the bolt...grind it down and keep only the bottom portion that operates the trigger return.

The firing pin release plate and it's location CAN serve a function but that function cannot be discussed here.

Sorry I kind of went on a rant, but I get a bit worked up over the way the GSG could have been GREAT right out of the box, and CAN be GREAT with the right work invested.

Anyway, no, do NOT remove your recoil springs.  The hammer strut is located in the trigger housing...but unless you are VERY familiar with how this goes together and how the parts operate I would not advise going in there and going to work with a dremel.

For those interested I suppose I could offer to do the strut mod, but to do so I would probably want the entire trigger group in hand to insure the mod is right and installation is right. 

Share this post


Link to post
Share on other sites

No rant at all; but a wealth of information. I am actually thinking of a way to create a animation video of the complete function cycle of the GSG-5. I wish there was one out there already.

Check out the last 2 minutes of this MP5 video where 'Gunny' explains the three basic types of machine gun operation: http://www.dailymotion.com/video/x8ri9x_tv-mail-call-mp5_sport.

Thanks again for sharing your knowledge, and I will post play by play pics later.

Share this post


Link to post
Share on other sites

Okay I finally got some photos with my iPhone, but I think the blurriness comes from a smudge on the lens.  Anyway I think one can see how the hammer strut has been deepened considerably.  Sorry, I didn't take a before shot.

post-173-144124370363_thumb.jpg

post-173-144124370365_thumb.jpg

post-173-144124370367_thumb.jpg

post-173-14412437037_thumb.jpg

Share this post


Link to post
Share on other sites

Okay, here are mine. I still have the 1/4" gap in the slide before contact with the hammer. Also, I noticed that the sear won't allow the hammer to go vertical. The trigger pull did feel a heck of a lot smoother though.

Hammer return spring is out. Where did I go wrong?

post-241-144124370373_thumb.jpg

post-241-144124370376_thumb.jpg

post-241-144124370379_thumb.jpg

post-241-144124370382_thumb.jpg

Share this post


Link to post
Share on other sites

Looks like you did an excellent job!  I think your notch is pretty close in depth to mine.

If you look at your photo set - picture #2 you'll see the problem.  You removed the rebound spring, but the rebound notch on the hammer is still there so of course the sear is snapping into it.

Now, when you actually drop the hammer from full cock by pulling the trigger the hammer will not land on the rebound notch...so as is your mod works.

IF you retract the bolt far enough to insert the chamber level - that little plastic piece designed to prevent the firing pin from hitting the breech block when dry-firing, you are pushing the hammer back far enough to get caught by the sear.  For this reason you have two ways to "test" your mod.  Way one, cock the weapon and let the bolt run forward.  Hold it open about 1/8" back from fully closed and pull the trigger.  The hammer will fall but the bolt being slightly open means the firing pin won't strike the breech block.  Then RELEASE the bolt to close.  Now gently start to tug back on the cocking handle and you will feel the hammer's spring force right there or just slightly back.

Way two would be to insert a fired case in the chamber, cock the weapon and pull the trigger letting the firing pin hit the case rim.  Then retract and note how the added pressure of the hammer/spring is right there when you start to cock the weapon.

A small amount of "play" isn't bad...remember before you did the mod you had about 1/4"of "slop" but now you may have just a few thousandths and that's a major improvement.  IF however you want the hammer right there, deepen the cut out in your strut a bit more....but take note that once you can no longer see excess metal when you rotate the strut in the hammer, you're done.

The way to NEVER worry about that rebound notch on the hammer again is grind it off and contour the hammer...look at my photos and you'll see my hammer has no rebound notch.

You did a good job!

Share this post


Link to post
Share on other sites

OH...your photo #2 shows the sear in the rebound notch...that's the one you grind away.  The cocked notch is the one behind that and of course you need to keep that one.  Sorry if I am stating the obvious but I just wanted to cover that base.

Share this post


Link to post
Share on other sites

I dont see any sear disconnect in those pics, where is it?

There should be a disconnect that moves the sear so that it is disengaged from the trigger if the bolt is not closed.

Ill have to post pics of the one in the sig, so i can show you what it looks like and how it works.

Share this post


Link to post
Share on other sites

OH...your photo #2 shows the sear in the rebound notch...that's the one you grind away.  The cocked notch is the one behind that and of course you need to keep that one.  Sorry if I am stating the obvious but I just wanted to cover that base.

Gotcha. Thank you.  :thumb:

Share this post


Link to post
Share on other sites

I am hoping this isn't a problem later. This is prior to trigger return notch being removed. Looks like the hammer was striking the front of the trigger housing. Pictures are slightly blurred but notice the mark on the hammer and the mark at the front of the left trigger plate. I also noticed that even with the notch present the hammer would stay forward of it due to the absence of a return spring.

post-241-144124370385_thumb.jpg

post-241-144124370387_thumb.jpg

post-241-14412437039_thumb.jpg

Share this post


Link to post
Share on other sites

DONE! No play at all. The instant the cocking tube contacts the breech the resistance from the hammer is felt.

I didn't grind the return notch in in angle that you did, but I made sure it was buffed and smooth.

Kilibreaux, does your GSG-5 eject a unfired round? Mine would not even eject a fired cartridge. I think the bolt is slamming the round in chamber too hard, and it is not giving the ejector enough to grab and eject the cartridge. If i place a spent shell in the chamber and ride the bolt forward it ejects fine. If I just let the slide slam forward, it will fail to eject. Could it be the angle of my grind?  :confused:

post-241-144124370394_thumb.jpg

post-241-144124370397_thumb.jpg

post-241-1441243704_thumb.jpg

Share this post


Link to post
Share on other sites

With your hammer strut modified, and the trigger unit out of the gun, the hammer will in fact rotate far enough forward to contact the forward edge of the trigger housing.  However, ASSEMBLED the hammer is prevented from rotating more forward than "vertical" because the bolt is in place.  This relates to an earlier comment I made that you could in fact grind the hammer pin notch on the strut completely away and have no functional problems at all because when assembled the hammer is prevented from "over rotating" by the bolt.  When disassembled however the hammer - if not cocked and held back by the sear would be free to rotate forward until contact with the trigger housing stops it.

If you examine the workings of a 10/22 you'll see that it's hammer strut has no hammer pin notch and when disassembled and the hammer released from the sear, it will rotate far enough forward to allow you to remove the hammer strut and spring.

As for your ejection problem, we come back to how blowback .22's work.  With a .22 the extractor really provides "secondary" extraction.  Primary extraction is when the gun fires and breech force shoves the bolt open...the shell is kicking itself out in point of fact.  Take a look at a Beretta M0d 21 and note it has no extractor.  The company touts the fact that it has a tip-up barrel as making it easy to load the chamber, but in fact this feature is really there to allow an unfired round to be removed from the chamber because there is no extractor to drag it out.  The gun extracts purely due to breech face thrust.  Well...so to do ALL .22's.  This is why when you fire live rounds the GSG "extracts" and ejects perfectly, yet when manually cycling the action you'll often end up with the shell still in the chamber.  Whether the bolt is allowed to slam forward or is "eased closed" will make a bit of difference.

If you look closely you will see that when the bolt is closed the extractor is cammed outward by the angle of the extractor slot on the barrel.  As the bolt opens the extractor - which has a sharp "hook" tip is spring loaded to move back inward and snag the rim of the cartridge, but here's the thing...when firing the shell itself has already pushed the bolt open so the extractor has ample time to engage the rim and add whatever "secondary" extraction is needed - mainly to anchor the outside of the rim to ensure/enhance ejection when the other side of the rim hits the ejector.  On the other hand, when "slow cycling" (because no human can rack the action anywhere near as fast as the gun does when firing), the extractor can slip off the rounded rim.

There are a couple of ways to approach this...you can go through the hassle of removing your extractor and carefully working the tip into a sharp(er) hook to better snag the soft brass case rim, or you can grab a miniature square file and carefully "hone" the extractor notch in the barrel to remove a few thousandths and improve extractor engagement.  Oh, you could also experiement with a stronger extractor spring.

Extraction of a fired case is generally more "sure" because the entire rim tends to flatten slightly creating better purchase.

Share this post


Link to post
Share on other sites

I thought maybe inertia had something to do with it. So you think there should be no ejection issues once live ammo is fired through correct? I know my extractor works fine because when I replace my SEF lower with the factory lower; with the OEM trigger pack  (unmodified) ejects a live round with no problems. That is why I though maybe the force of the hammer against the breech was possibly forcing the cartridge further in that intended. Kilibraeux, does your GSG eject live rounds?

post-241-144124370404_thumb.jpg

Share this post


Link to post
Share on other sites

It does but not consistently.  As I said, the extractor is pushed out, away from the rim by the beveled extractor slot in the barrel.  This means that when you work the action the extractor must move inward by spring pressure to snag the cartridge and even then, the extractor hook has minimal purchase on the spot where the cartridge rim and case meet.  Something I didn't mention previously is the extractor could have it's outside surface trimmed down so it settles as deeply as possible in the extractor slot during action operation.

Remember, during actual firing the cartridge is being shoved out of the chamber and the GSG does extract quite well - at least mine does.

Share this post


Link to post
Share on other sites

I see what you meant by self extraction. If I pull the slide back fast (not nearly as fast as id the gun was actually cycling during fire) the round pops out of the chamber just from the speed of the retracting bolt.

I didn't take a photo but I also re-shaped the grind of the hammer more to the angle of the sear. The trigger action feels sooo much smoother.

I have 29 years of firearms experience but never got into modifications or armory until I acquired my GSG-5.  Then again come to think of it, I never had to prior to the GSG-5.

Thank you for all the help, you are a wealth of f knowledge. I can't wait to take her out to the range.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...