Feed ramp geometry fix.

This was part of an original set of photos submitted to Arsenal for the Sam 5 and Arsenal 106 rifles. The Bulgarian 5.56 weapons use an AKM feed ramp geometry unlike the Russian or Polish 74 style technology. There are also three different generation of Bulgarian 5.56 magazines. Gen I had the ear tabs milled off, Gen II had slight ear tabs, and Gen III had near full ear tabs. The ear tabs simply help to push the nose of the round to center. This feed ramp bevel fix will allow all three generation of 5.56 Bulgarian magazines to feed reliably in your system.

Tools needed; Dremel Tool with a slow speed setting and 1/2" round stone bit along with a 1/2" cotton drum with jewelers rouge for final touch up. Lay the Dremel facing toward barrel on the inside the receiver rails to steady the tool. Then simply move the bit into position allowing the receiver rails to center the Dremel. The key is to not actually change the shape of the chamber itself leaving the casing unsupported, which is dangerous. You only want to take metal off below the areas of the Bulgarian original feed ramp bevel.

Disclaimer; Fixing the rifle yourself can void your warranty with Arsenal if your rifle is still within the warranty period. In some cases it might be better to have Arsenal do this fix for you. If you are confident in your abilities then by all means proceed. Make sure to hand feed quite a few rounds from both sides of the magazine to see exactly how wide and low the bevel needs to be. Use several magazines to get a realistic picture of where the rounds are hitting. Also remove your firing pin to be safe, which is held in by a simple pin on your bolt, easily drifted with a center punch.

RR  

RetroRevolver77, those are truely EXCELLENT slides, and PERFECT advice on how to deal with the classic 106 barrel feed ramp issue.  Thank you for posting them.

The process to diagnose the issue is indeed simple... remove your firing pin, strip down the rifle, ride rounds forward with JUST THE BOLT, and look - REALLY LOOK, and what the bullet wants to do.  AKs are wonderful:  98% of their issues can be solved by simply LOOKING, slow and careful, at what they are doing.

As the 106 series tends to exhibit nose impact on the right, left, top, and sometimes bottom of the ramp?  It's critical to try SEVERAL mags, look for a pattern, then work on the area of the barrel ramp that is least reliable.  I believe properly informed owners can do this job better than Arsenal can:  They don't have all of your mags :)

I did mine today. I tried the first gen Bulgie mags and as you stated the bullet fed straight  and hit the flat face of the barrel/chamber . Then with the Gen 2 Bulgie mags with wings it fed fine. But I went ahead and opened it up like in the pic you posted. Now I used a grinding stone/dremmel and then came back and polished it. It don't look  nearly as good as your job. Mines actually UGLY. Almost where I thought I screwed up. But I checked it out and it work great with both Gen 1 & 2 mags. I had the jamming and bullet set back on the Gen 1 mags. This should cure the issue. Thanks WarDawg

Photos don't show up. Could you please rehost them?

No pics........

Anyhow, my SLR106FR was bought used with 6 mags, 2 of which wouldn't feed.  Now I know that they are Gen 1 and would hang up the rounds on the left side of the stack.
5 minutes with the dremel later and VOILA!!! a kickass reliable accurate fighting carbine!

I didn't take pics, but I used the extension to get my stone and polish tips right where I wanted them.

It doesn't take much, as with all metal removal, take a little off and test/measure.  Its much easier to take a little more off than put a little back

I fixed it. I moved them into a sub account with Photobucket and for some reason it changes the link.

Much improved. Of course, according to the photo captions, slides 1, 2, 4, and 5 are missing.

This is only an issue with Gen 1 mags, right?

Originally Posted By Swindle1984: Much improved. Of course, according to the photo captions, slides 1, 2, 4, and 5 are missing. This is only an issue with Gen 1 mags, right?

Some of the slides were originally submitted to Arsenal during development of the 106 series. I had the only working proto-type stamped 5.56 Bulgarian prior to the 106 release. In an agreement, certain elements were left out of this discussion on purpose. The feedramp fix improves feeding through any of the host weapons using all three generation of magazines. Remember Russian 5.56 rifles use 74 geometry while Bulgarian uses AKM.


RR

I only have gen 3 mags. they are the smoke colored ones. I have never had a stoppage with this rifle. so I'm glad I didnt have to figure this out when they were more new than they are today. I've tried converted 5.45 mags and they suck. but with the gen 3's my rifle will even cycle m200 blanks that the US army uses. that really surprised me.

Anyone know when Arsenal implemented a fix? I'm looking at a 106cr that has a KT prefix and was wondering if it was GTG.

So I posted this in troubleshooting, I'm having an issue like this with a 7.62 not feeding hp. But what I can't find an answer on is will this hurt the integrity of a Crome lined chamber and barrel? I.e start the Chrome chipping away?

I'm not sure if, or when, the fix was implemented. I just picked up a SLR 106 pistol brand new, and it was basically a bolt action gun until I modified the feed ramp.

Az

Thread is over 6 years old...I hope they did something.

Starting with the BD serial # prefix there are no longer any feed ramp or "canted" sight issues. Hope this helps, Bob.

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this mod is a case blowout waiting to happen.
 

No, because you simply remove material below the original feed ramp. You don't alter the existing feed ramp in any way. This is the mod that I developed that Arsenal incorporated into all the new production 106's to address this feeding issue.

Thanks!  Found a correct prefix rifle!

My new rear converted Saiga in 5.45 had the same exact issues which I notice the first day out of the box. I phoned Century and sent them photos  then received a RAN number & shipping label. to send it back. Two weeks later it came back with the same as shown chamfer. This issue is now common on the 5.45 rifles and is not a mag issue as I had tried 3 different mags on mine.Other people on other AK Forums are having the same issue with the rounds hitting the end of the barrel flatting out the bullet tip. I "think" the root cause is a incorrect bullet guide as this is a recent across the board problem ? My other 5.45 Saiga's feed just fine.

Either way thanks for the how to fix !