Jump to content

Low Brass Frustration


Recommended Posts

OK, I've done everything I can think of.

 

I've polished the bolt and carrier and hammer (Tapco G2, modified by CSS to fit Saiga). Pulling back the charging handle is smooth, and the bolt will ride forward with no hesitation.

 

I'm using the stock springs and spring guide.

 

I drilled out the gas block so that all of the ports in the barrel are visible and clear.

 

I've tried the stock gas puck, the CSS reliability kit puck, and the MD Arms booster puck.

 

My gun has 4 ports, which I've enlarged to .110" so far.

 

The barrel is the stock 19" with a Phantom flash hider attached.

 

And with the stock plug, the CSS plug, and the auto plug, it will eat any high brass like candy. But it only cycles Winchester bulk pack about 50% and Federal bulk pack about 95%.

 

I have one factory 5-round mag, 5 CSSPECS 8-rounds, 3 12-round Promag drums, and 2 20-round MD drums. The factory and CSSPECS mags cycle the low brass the best, but still not 100%. All magazines cycle high brass fine, as long as the gas is set sensibly.

 

I suppose I could drill the ports even larger, but .110" seems borderline excessive already. Any suggestions on additional things to try before I do something drastic?

 

I'd prefer not to use lighter-than-stock springs.

Link to post
Share on other sites

What Heartbreaker said. What aftermarket parts do you have on it? Pictures of your profiling and polishing work?

 

Check that. I just looked at the picture of your gun in the picture thread. Try the factory hand guard.

Edited by YOT
  • Like 1
Link to post
Share on other sites

I've verified that the quad rail isn't binding the gas tube. With the gas block off, the gas tube can slide fore and aft with the rail mounting clamp installed and tightened. It's clamping the barrel, but not the gas tube.

 

When I hand-cycle the action and let the charging handle forward slowly (letting the springs push it forward instead of my hand) the only place there is any sticking whatsoever is when the extractor hits the front of the slot in the trunnion and detents out when the bolt carrier is about 1/2" from the fully forward position. And it only does that if I ride the handle forward slowly.

 

Here's my bolt, carrier, and hammer:

 

post-50825-0-61699300-1455586503_thumb.jpg

 

post-50825-0-23098200-1455586504_thumb.jpg

 

post-50825-0-80115000-1455586504_thumb.jpg

 

post-50825-0-10551100-1455586719_thumb.jpg

 

I rounded off the angular corners of the bolt, carrier and hammer, but didn't remove huge amounts of metal on the theory that it's easier to remove more than to try to put stuff back. It feels much smoother than when I got it, and the only place where the action spring won't ride the bolt carrier slowly forward is where the extractor hits the front of its groove in the trunnion and detents out.

 

Thoughts?

Link to post
Share on other sites

Your hammer looks pretty rough.  Your going to want to round out those edges where it is smooth.  See if that helps and go from there because that is not the norm considering those ports.   Those are some big ports.

 

Also, this happened to me and it boggled my mind for awhile.  The pin that holds the bolt head to the tail of the bolt came loose and was dragging on the carrier creating a lot of drag.  I had to put it back in and peen it out until it stayed.  The pin will make a noticeable groove in the carrier when it cycles if this is the case.  Not a common problem I think, but it happens.

  • Like 1
Link to post
Share on other sites

That G2 hammer should atleast, mimic the profile of the OE hammer.

Put your OE hammer back in and see if it acts the same.

 

Are you seeing any excessive wear, where the bolt carrier enters the rear sight block? Too much contact pressure there, can really drag the action down.

 

Those ports are massive, curious why or how you decided on that combination?

 

Edit; also, clean all that Shit paint from any and all contact points inside the receiver.

Edited by Mullet Man
  • Like 2
Link to post
Share on other sites

This is mine. I did it myself with a dremel and polishing wheels long before I knew of a that performs the service. It's dirty. I just took the pictures. No biggie. Whether I did it right or wrong, it works 100% with all shells, the autoplug adjusted for federal bulk pack stuff. A 180 of the plug for slugs and buck.

 

E1435F2A-E261-4D09-A0A9-8064B201BC8D_zps

 

F6BFAC38-4D6F-4F46-B5EE-C3A351621BDE_zps

 

0DB5BC3D-7BF3-4941-A397-AFB5ED14D31E_zps

 

F2C6BA6B-C3E4-43F4-81EE-5D95F1DF4D09_zps

  • Like 2
Link to post
Share on other sites

What Heartbreaker said. What aftermarket parts do you have on it? Pictures of your profiling and polishing work?

 

Check that. I just looked at the picture of your gun in the picture thread. Try the factory hand guard.

I was thinking this a while back, but no one ever wants to hear it.

  • Like 2
Link to post
Share on other sites

 

What Heartbreaker said. What aftermarket parts do you have on it? Pictures of your profiling and polishing work?

 

Check that. I just looked at the picture of your gun in the picture thread. Try the factory hand guard.

 

I was thinking this a while back, but no one ever wants to hear it.

I've ruled out the handguard as a possible factor. It's clamping on the barrel, not the gas tube. Installing it had no effect on cycling--it didn't make it any better, but it didn't make it any worse, either.

 

There are no pins coming out of the bolt dragging anywhere on the carrier or action.

 

The paint on the rails wore off the contact points long ago. I haven't cleaned the action since the last range session Sunday afternoon.

 

I looked at the hammer more closely, and it is moving about 3/16" away from the disconnector as the carrier passes over it, so a lot more material can be removed before there's any danger of trigger problems. I'll pull it and compare to the factory hammer more closely, and round off the angles some more.

  • Like 1
Link to post
Share on other sites

DO NOT touch the gas ports anymore. Your issue is somewhere else. I've had and have a Saiga 12 with smaller and obscured ports that cycles walmart bulk on both settings with the stock puck and gas selector, springs, hammer, no polishing, and no lube. I rewelded the original trigger and used it also.

 

Make sure whatever rail or handguard you have on there doesnt block the gas block vent. That could slow down the puck enought to cause a failure.  

 

Hand cycling doesnt say much since the carrier is forced straight back during operation and you can feel the op rod rubbing inside the gas tube if you hand cycle the carrier.   

 

Drum magazines have a higher tension and can also slow the carrier down.

 

Im almost sure it is going to be that Tapco FCG that is causing the failures. No matter how much you polish, the tapco trigger holds the hammer higher and adds resistance to the carrier when the gun cycles. If your gun was barely able to cycled low brass out of the box, the added resistance and incorrect hammer geometry can and will cause problems.

Polishing helps cut down that resistance. Some get lucky using an AKM style FCG like the Tapco, others dont.

 

You may not want to hear it but put back all the stock gas system parts and work from there.

 

The only drastic thing you should be doing is looking for a replacement barrel to anticipate the metal between the ports cracking.

 

I have a Vepr FCG id be willing to give you to try if you pay for shipping.

Edited by ElHuron
  • Like 1
Link to post
Share on other sites

He hasn't done the second thing you do automatically. He hasn't Profiled his hammer. Instead, he just got parts of it smooth and shiny. Old story that comes up every now and then. 

 

-I tried everything but the most obvious first thing you do, that every one said to do. Now what?-

  • Like 4
Link to post
Share on other sites

YOT, I'm not ruling things out because I don't think the ideas have merit, I'm ruling things out because I've already tried them and verified that they are not the cause of the problem.

 

After comparing your hammer to mine, I pulled it out and rounded the corners so it looks like yours. When the bolt carrier comes back, it's now going about 1/16" past the disconnector catch instead of the 3/16" it was traveling before, and I made sure the hammer still hits the bolt tail squarely. The change in geometry seems to make the hammer easier to cock.

 

The handguard is a free float. There is about 1/4" of space between the vent hole in the gas block and the nearest piece of handguard. There's more clearance around the vent hole with the rail than with the stock handguard.

Link to post
Share on other sites

You have not eliminated the rail as a problem - that can only be done by trying it WITHOUT the rail. Also, will it cycle the low brass with the butt against a solid object?

If so, then you are loosing energy as the gun is recoiling and running back with the bolt. A firmer hold or some weight in the stock will help.

  • Like 2
Link to post
Share on other sites

You have not eliminated the rail as a problem - that can only be done by trying it WITHOUT the rail. Also, will it cycle the low brass with the butt against a solid object?

If so, then you are loosing energy as the gun is recoiling and running back with the bolt. A firmer hold or some weight in the stock will help.

 

 I've test-fired with the rail and the factory handguard, and there was no difference in cycling, so yes, I've ruled that out as a variable.

 

A loose grip/hold degrades reliability with Federal low brass from 95% to about 50% with the factory 5-round magazine. My expectation is that with the gas ports the size they are, it should be able to cycle Winchester bulk pack reliably even if held one-handed by a kindergartener, without chaining it to a tree or filling the stock with lead.

 

No recoil buffer.

Link to post
Share on other sites

There is something going on that is far from correct. If I could see it first hand I could probably tell you in all of a few seconds what it is. Instead, I keep coming back to this thread frustrated as I am sure many others are.

 

I see nothing but great advice here. Take some of it regardless of whether you tried it before or not. Try all of the great advice at one time.

 

remove paint from inside

lose quad rail

run factory puck and gas regulator (make sure gas reg is on setting "2" with weak loads)

re-profile the hammer

a little light lube (oil) might help as well, no grease

  • Like 1
Link to post
Share on other sites

How is the inside of your gas tube looking?  Make sure that its not too heavily fouled up.

 

Also can you be more specific on the types of malfunctions that you are getting?  Is the shell getting stuck and pinned by the carrier when shooting, like a stovepipe?  Does it even pull the spent shell out of the barrel?  Does it eject them sometimes?  If so how far do they eject?

Looking at the spent shells will also give you an indication of what is happening. 

Edited by incognito485
Link to post
Share on other sites

Are there any signs of wear INSIDE the gas tube? That can be a source of friction if the tube is not square to the rails. Last place to look is the recoil spring and guide -there is a replacement that will work better than the factory with wussy shells. I do not reacall who makes it, but one of our regulars will be along to give a link.

Final answer - shoot better ammo!

Link to post
Share on other sites

http://www.nssfblog.com/firstshotsnews/shotgun-shells-explained-the-new-shooters-dictionary/

 

Clip: "The High Brass vs. Low Brass Myth

If you’re a new shotgun hunter, one of the things you’ll notice in retail stores are boxes of shotshell ammunition marked “high brass.” This high brass, the portion of the shotshell that houses the primer and holds the plastic hull, is the source of some old wive’s tales that just won’t go away. Let me explain.

When I was a younger man, I was taught that the difference in the height of the brass rim was indicative of the power or velocity of the shotgun load. The longer the brass, the hotter the shell and the faster the shot traveled after it left the muzzle. High brass was more powerful than low brass. That may have once been true, but not anymore. When purchasing shotgun ammunition, ignore the length of the brass rim and pay attention to the labeled velocity and payload of shot (again, stated in ounces) of the shell."

Edited by patriot
Link to post
Share on other sites

I test fired the Saiga today.

The hammer reprofiling seems to have done the trick. With the CSS 6-position manual regulator in position #6, I was able to run a full MD-20 drum of Wal-Mart Federal 1-1/8oz bulk pack with no malfunctions, average ejection about 5 feet.

I was also able to run a MD-20 drum of Wal-Mart Winchester 1oz bulk pack with only 1 FTE, average ejection 2-3 feet.

 

I still need to get the Tac-47 auto plug adjusted so that it will run both bulk pack low-brass and 3" magnums reasonably But I ran out of ammo and daylight...

  • Like 1
Link to post
Share on other sites

I've already gotten the gun pretty well broken in (about 500 rounds so far, ~300 of which were 2.75" high brass or 3" magnums), so it's not going to slick up much more than it already is unless I grind even more off the hammer. But I don't plan on doing that because if I did, the hammer probably wouldn't catch the disconnector any more.

 

I'm planning on having the barrel shortened, and the Phantom flash hider permanently attached to bring the barrel to 18.25". So those extra-large ports may come in handy.

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.

Loading...
  • Chatbox

    Load More
    You don't have permission to chat.
×
×
  • Create New...