Yeah...I'd wait to dump that time and money into that rifle. I was just given some good advice on that, if you go messing with port size and make it too big, well then you're screwed.
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I seriously screwed the pooch on something that will help you out in this situation. I overport barrels for function testing to mimic high cycle rates from suppressed good ammo systems.
You can do this with a hand file or a dremel, but the area of the gas key where the tube goes in, if you open that up the smallest amount you lose what you gain by stepping up port diameters. Or you can file down the tube od right there.
1 to 2 ejection is moving, the fact that you can even run a H3 means you've definitely got some residual energy. I like them that way.
If you think Wolf is weak, try Tula, holy cow that stuff barely pushes the projectile out the barrel.
I would think you could leave your upper the way it is and work on the follower/spring in the bolt hold to work this out.
*oh yeah, sometimes a steel cased ammo helps extraction because it doesn't expand in the same manner so this may throw another variable besides just being weak ammo
Put my new blue spring in and only had a few failures to lock back while shooting 855. Still does fine with Wolf. I ordered a BCM full auto carrier with key since the BCG is out of stock and will see how it does. While looking at carriers on LMT's site, I noticed the enhanced carrier had 3 vent holes instead of 2. Sooo, I will machine the 3rd hole in the DPMS one and see what it does. Would be the same as enlarging the keys tube hole. Vent more gas. Should make it more tuneable I would think.Go lighter with the buffer and spring.. If it don't work I won't be out anything. I am going to buy a better quality carbine as soon as I find what I want. BCM has most of their uppers out of stock and won't even take orders for completes. LMT has stock, but I don't see the selection that BCM has.
EE,
I don't want to rail on your parade. I really like BCM stuff and use it for many of my projects. But, there are plenty of other options.
Did you know that you can get a complete Colt 6920 upper with BCG for 685.00? http://www.coltsmfg.com/ShopOnline/t...35/Rifles.aspx
Drop that onto your lower and you are now good to go. I think you should simply quit chasing the unicorn and sell the upper as is and be done with it.
I think i have to agree...its a dpms...fine plinking gun but i wouldnt pile all this time and headache with a colt, bcm, dd and any other make. Send the sob back to them like they recommended and let them fix their f up. Or you could do what i did, sell the sub standard rifle and get a BCM
Problem solved!!! First I went to Grice Gun shop here in PA and they actually had a LMT SPM and STD on the shelf. I got the STD, the SOPMOD stock and their grip sold it for me. Freakin awesome. Shoots great with my EOTech 512. Very nice gun. All the staking was proper as expected. Fit and finish perfect.
Second, my BCM F/A carrier and Magpul mags came in today. Put the new carrier in the DPMS and shot 40 rds one at a time using just the metal mags I've been using and just m855. No problems what so ever and for what it's worth, all my brass was in one tight area at 4 0'clock, which is exactly where the LMT's brass landed too.
Thanks all for the advise
So, not the gas port?
I believe the gas port is too large since it took a H3 buffer, Blue buffer spring and full auto carrier to get the BCG to slow down and lock like it's supposed to. Like I said, now the cases eject in the place as my new LMT and that's all the parts I changed. Plus, before I changed the carrier, the buffer and spring made a big difference. Now with the F/A carrier it ejects just like my STD. It probably wont cycle Wolf anymore like it is, but a quick buffer/spring swap would fix that.
Or, maybe just a poorly made BCG, not unheard of DPMS.