FTEs on a franken

**shogun** · 08-21-14, 21:00

I have a basically newly assembled franken AR which was assembled 2 years ago, tested using 200 rounds, and then kept until now. Major parts include:

BCM 16in mid length barrel
LMT standard full auto BCG
Elisco (licensed by colt couple of decades ago) select fire lower
LMT full auto lower parts
Carbine buffer and spring

The rifle was tested right after it was assembled and nothing untoward happened. I then disassembled it, wiped the BCG clean and ran a few patches in barrel and kept it in a safe until now. Last week I brought it in the range on impulse and experienced two really annoying FTEs after the 50 round Mark.

One FTE was while firing full auto and the extractor didn't get over the case rim. I could pull the charging handle freely. I had to use a dowel rod to push the spent casing out of the barrel and saw that the rim of the cartridge wasn't torn.

The second and really bad FTE was while firing on semi. A case got stuck again but this time the charging handle couldn't be pulled. We didn't know yet if it was indeed a cartridge or a live case so We couldn't use a dowel rod. Trying to hammer and push the BCG down wasn't working so we had to disassemble the buffer tube to relieve the pressure on the BCG and get the case out. The guys in the range were suspecting a popped primer lodged in the charging handle but I didn't catch it after getting the BCG out.

Could the FTEs have been caused by lack of lube? The gun was last lubed maybe 6 months ago using Mpro7 which is really thin. I touched the BCG before firing and there was only very little left.

I was using government arsenal ammo (we get that a lot here). 5.56 55grain, 00 vintage. The boxes of some of the rounds were already tattered so maybe the rounds were causing the problems?

How do check if the extractor functions correctly? I used regular motor oil 2 years ago and didn't degrease the BCG when cleaning. Maybe the oil gummed up the extractor?

This is really annoying, hopefully I can get this sorted out. I will prep the gun better and use better ammo next time. Things like this ruins the trip to the range!

**Heavy Metal** · 08-21-14, 21:06

Phillipines?

**shogun** · 08-21-14, 21:19

Yep! you can tell by the Elisco?

**Heavy Metal** · 08-21-14, 21:26

What I thought. I would replace the extractor and spring with a heavier spring or a MGI D-
Fender and would try and run an H-2 buffer.

**shogun** · 08-21-14, 21:32

Thanks! I don't think we get the MGI D-fender here, will the regular circle extractor o-rings work the same? I will shop for a spring upgrade kit.

As for the H2, the goal is to make the bolt go in to battery faster/ be more forceful?

**Heavy Metal** · 08-21-14, 22:42

No, it is to slow down the opening of the bolt on the recoil stroke to make the extractor's job easier.

**Iraqgunz** · 08-22-14, 01:21

I would polish the chamber just for shits and giggles. Then I would search for an H or H2 buffer plus an enhanced extractor spring. An O-ring or defender isn't needed.