BCM BFH 14.5 Mid Problem

[Sparky5019]

OK,

I finally got this barrel a few weeks ago and went to install it. I set it up in the jig and drilled and reamed the FSB taper pin holes and the FSB is standing straight and completely true; I was proud of that one seeing as it was the 1st one I had done. Installed the gas tube, etc, etc.

Now for the problem...



I slide the bolt carrier in with no trouble and put the upper on the lower only to find out that the bolt lugs won't go through the recesses in the barrel extension every time unless the bolt is TOTALLY forward in the carrier, and then only barely.

If I lock the bolt back then lower it with the charging handle (so as not to slam it down), it will still catch and not go into battery as shown above. If I pull the carrier back using the charging handle and lower it as above, it MIGHT slide through and go into battery.

I checked the alignment pin in the upper and the slip fit of the extension in the upper is tight. The alignment pin is top center (the BRDE FSB jig indexes off the alignment pin) and the FSB is straight and on top of the gas port (which is 0.078" btw). The M4 feed ramps in the extension line up perfectly with the upper. The only other thing that I noticed is that putting the BCM Mod 1 comp on with a crush washer, it would not turn up correctly once making contact with the washer. Since it will be pinned and welded, I'll need to get some spacers anyway so that's no big deal.

These 2 things got me thinking...could this be a bad barrel or do I need a BCM BCG for ANY BCM barrel? I've never had problem 1 out of any BCM stuff I've bought but this is the biggest part of their's that I've used yet.

The gun is a CMMG and has run like a sewing machine for several years with absolutely NO trouble; not even 1 jam.

Anyone had similar experience?

Thanks!

Sparky

[uncle money bags]

What has BCM had to say about it?

[nickdrak]

Take a pic of the upper without the BCG to show the alignment of the gas tube inside of the upper receiver.

[Sparky5019]

Ill have to take that pic tomorrow but I checked and it line up perfectly and goes straight through the upper (not angled). The gas key is tight to the carrier and the screws are staked correctly.

I took the bolt out of the carrier and checked the carrier motion; it's perfect.

The hang up is the bolt lugs on the extension as I described when the bolt is not completely forward in the carrier.

I'll try to get that pic tomorrow night after the match.

Thanks!

Sparky

[P2000]

Does it do this with a different BCG?

[MistWolf]

Check inside the barrel extension for FOD. Double check to make sure the gas tube floats where it passes through the barrel nut & enters the upper receiver.

Do you have another upper you can test fit the BCG to?

[Iraqgunz]

Please contact BCM. Do not be surprised if you are told (sorry) since you modified the weapon.

Once you have their response we will revisit this.