FBMG range report

[macbeau 902]

I took my 6 FBMG mags to the range yesterday and function-tested them with a variety of ammo. All took 20 rounds (22 in the case of the one where I swapped in my 8 round follower converted to 10 rounds) and worked flawlessly with SA, Pakistani, 70's POF Indian and GA Arms 168 HPBT match. No runs, no drips, no errors.

However, about a week earlier, a buddy of mine took my S-308 to the range with one of these mags to test out for me and had problems with short-stroking of the bolt, resulting in stovepipes and not re-cocking the FCG. I had never had any problems with this rifle or with the factory 8 (10) rounders and there was no other obvious flaws. My buddy speculated that I was having problems with the geometry / installation of my FSE FCG. Upon futher inspection, however, I discovered that the firing pin retainer pin had "walked" out through the top of the bolt and was binding against the front, underside of the carrier. It wasn't sticking up by much (maybe .010" or less), but it was enough to tie up the rotation of the bolt during cycling and "retard" the carrier stroke. It made disassembly tough too. The wierd part was that I pushed the pin back in with a small finishing nail and a little finger pressure. The cycling of the action, however, wasn't enough to push it back in. I need to find a way to secure it a little better and still be able to remove it when needed.

If you have been experiencing problems like this, check your firing pin retainer pin. It should be flush, if not slightly countersunk, in the top of the bolt head. Just FYI.

Hopefully, I'll be able to post pic's of what I am talking about this evening.

(*note) - Here are the pic's. The first two pics show the malfunction mentioned above. The second two show how the firing pin retaining pin "should" be situated. The last one shows the scoring on the cam slot in the bolt carrier from the upward-protruding firing pin retainer pin...*)

Edited January 17, 2007 by macbeau

[SOPMOD 254]

I took my 6 FBMG mags to the range yesterday and function-tested them with a variety of ammo. All took 20 rounds (22 in the case of the one where I swapped in my 8 round follower converted to 10 rounds) and worked flawlessly with SA, Pakistani, 70's POF Indian and GA Arms 168 HPBT match. No runs, no drips, no errors.

However, about a week earlier, a buddy of mine took my S-308 to the range with one of these mags to test out for me and had problems with short-stroking of the bolt, resulting in stovepipes and not re-cocking the FCG. I had never had any problems with this rifle or with the factory 8 (10) rounders and there was no other obvious flaws. My buddy speculated that I was having problems with the geometry / installation of my FSE FCG. Upon futher inspection, however, I discovered that the firing pin retainer pin had "walked" out through the top of the bolt and was binding against the front, underside of the carrier. It wasn't sticking up by much (maybe .010" or less), but it was enough to tie up the rotation of the bolt during cycling and "retard" the carrier stroke. It made disassembly tough too. The wierd part was that I pushed the pin back in with a small finishing nail and a little finger pressure. The cycling of the action, however, wasn't enough to push it back in. I need to find a way to secure it a little better and still be able to remove it when needed.

If you have been experiencing problems like this, check your firing pin retainer pin. It should be flush, if not slightly countersunk, in the top of the bolt head. Just FYI.

Hopefully, I'll be able to post pic's of what I am talking about this evening.

(*note) - Here are the pic's. The first two pics show the malfunction mentioned above. The second two show how the firing pin retaining pin "should" be situated. The last one shows the scoring on the cam slot in the bolt carrier from the upward-protruding firing pin retainer pin...*)

 

 

Have you gotten a chance to do any more mag testing? Especially the one with the short follower

[dasu 1]

nice review!

[macbeau 902]

Oddly enough, I shot the "22-rounder" this past weekend. I put another 66 rounds through it without a hitch. (on any of them, I would recommend hitting the inside with some dry silicone spray). My round count for the 22-round mag is right around 400 now. I have about 100rds out of the others. The only malfunctions I've had are attributable to the firing pin retainer pin problems mentioned above.

[Bvamp 604]

I had a loose pin in the bolt head of my s12. it is a little different in design than your regular ak type, as it has two parts to it. only the front part rotatates. ANYWAY, I had a pin in there that was WAY too easy to push out, so I secured it with blue locktite. it comes out no problem, but you now have to tap it out with the drifting tool and a small hammer or screwdriver handle.

[SOPMOD 254]

Oddly enough, I shot the "22-rounder" this past weekend. I put another 66 rounds through it without a hitch. (on any of them, I would recommend hitting the inside with some dry silicone spray). My round count for the 22-round mag is right around 400 now. I have about 100rds out of the others. The only malfunctions I've had are attributable to the firing pin retainer pin problems mentioned above.

 

Well since you have done half of the MRBS testing for me I'll have to get a case and do the other half of the testing myself

 

22rds is better than 20rds if only a tiny bit

[macbeau 902]

Well, Gee! Thanks!... I guess!?!?!!????

I just wanted to see if the followers from factory mfg'd 8-rounders that had been modified to 10-round capacity would work in the FBMG 20-rounders - seeing as how they used factory followers in the 20's. I really did wanna see if they'd work and I am very much satisfied! I will be happy to give details to those that ask, but - for the most part - I used South African, 83 headstamp, ammm that I got from AIM about 7-8 months ago. I also used Pak, Indian, and Georgia Arms Match... Again - caution anyone from modifying their mags (least they void the factory warranty) and I would encourage the use of some sort of "dry silicon" lube in inside of the mag's as they are kinda dry as you get them from FBMG. Also - be aware that any malfunction you may experience may be from something else (probably simple) in the rifle ... and, not necessarily the Mag or ammo's fault. I know that seems like a mush-mouthed response, but the S-308 has a way of "working itself loose" and doing strange things... see above. (IYKWIM).

I have no problem recommending the quality, fit and function of these mags, but you need to look after your rifle too... Just fyi.

BTW- I also added "blue loc-tite" to my firing pin retainer pin, after a through degreasing, and have had no problems ever since...

 

Thanks for reading,

Macbeau sends...

 

Oddly enough, I shot the "22-rounder" this past weekend. I put another 66 rounds through it without a hitch. (on any of them, I would recommend hitting the inside with some dry silicone spray). My round count for the 22-round mag is right around 400 now. I have about 100rds out of the others. The only malfunctions I've had are attributable to the firing pin retainer pin problems mentioned above.

 

Well since you have done half of the MRBS testing for me I'll have to get a case and do the other half of the testing myself

 

22rds is better than 20rds if only a tiny bit