recently put a ar-15 6x45 together with a bhw 20" barrel. used a carbine collapsible stock kit, low profile non adjustable gas block. i have used the lower and upper on other builds. gas rings are ok, gas block is centered, checked 3 times. buffer spring, buffer and tube came in a kit. also switched to a a2 lower with same results.
here is what i have done, loaded a single loaded round in the magazine, chambered it and fired it. the case ejects most of the time to the 3:00 position but if you tap the side of the upper the bc will drop. if you use the t handle it locks every time. it ejects about 80% of the time but not 100%.
i am using handloads with 70 gr balistic tips at 3010 fps and 80's at 2845 fps so they are not light losds.

under gassed????? your thoughts and solutions.
thanks in advance.

quote:

under gassed?????

Sounds like that to me.

Also make sure you have the proper buffer and spring for the right stock

buffer and spring came in an anderson kit.

I'm not familiar with your particular components but sounds under gasses of over spring'd to me.

spring is a std carbine with 3 ounce buffer. rifle has a rifle length gas tube.

If you have a 5oz buffer see if tha makes a difference.
Have you measured the gas port?

have not measured yet, it currently has a h2 huffer in it. i switched out the 3 oz to see if it made a difference

As others have said I would fiddle with the buffer weight before anything else. Quick question, was the barrel pre dimpled for the gas block? I only ask because on my last build the gas bock need to sit a bit off of the step down to the gas block to align correctly.

In anything other than a standard caliber (ie 5.56 or .308 for an AR 10) I highly recommend an adjustable gas block.

What you are describing is caused by insufficient gas to push the bolt back far enough for the magazine follower to fully lock the bolt to the rear.

There are numerous adjustable gas blocks out there and you should be able to tune your load to your rifle. Keep in mind that in semi-auto rifle fast rifle powders will also cause the conditions you describe. You generally want something with a burn rate in the middle of the spectrum for reliable cycling of the action. Slow magnum type powders also aren't good in semi-autos. AA2200 worked really well for me with a 6.8SPC in an AR platform. Not sure how it would work in a 6mm

well haven't made a lot of progress but i did blow thru the tube but it pretty much verified the markings i had placed on the barrel with a pencil. one thing i did notice is it moved the block forward, the port in the tube isn't centered in the center of the set screw hole. it is much closer to the back edge of the set screw hole. can't tell if it is partially covered in the gas block. tube is a wilson combat.
not sure if this can affect function or not. also i see a little carbon where the tube goes into the block.

quote:

Originally posted by bug hole:
well haven't made a lot of progress but i did blow thru the tube but it pretty much verified the markings i had placed on the barrel with a pencil. one thing i did notice is it moved the block forward, the port in the tube isn't centered in the center of the set screw hole. it is much closer to the back edge of the set screw hole. can't tell if it is partially covered in the gas block. tube is a wilson combat.
not sure if this can affect function or not. also i see a little carbon where the tube goes into the block.

Had the same thing on a friends AR he brought it to me saying it stopped working.

Did the normal Armorer checks found the gas tube loose.

Fixed it rifle went back to functioning properly.

Your seeing carbon and it is loose.

I would fix those problems before anything else.

Well found the problem, I checked the key on both sides and no leak found. When I disassembled the bolt I noticed carbon at the front of the Key. Switched out the carrier with another one I had. Ran like a well oiled sewing machine.
Now I have to fix the other key