Anyone have a suggestion on selecting a bolt/carrier assembly for my ar? i'm looking for something reliable but not outrageously priced (if that exists). no sales pitch please. just personal experience would be helpfull. i'm a horse's mouth kind a guy. this is the last part i need in the quest for evil rifle fun time! thanks.
Well, a name brand bolt carrier and bolt is about the same from a function point of view. I've got a Colt factory rifle, I built a match gun up sing DPMS parts / receivers, bolt carrier etc. with a Kreiger Match barrel. I saw no difference in function one over the other. The DPMS carrier group I got was chromed for easier cleaning. It does clean easier than a parkerized steel bolt carrier and bolt.
Lastly I have a Del-Ton Middy upper that I built into a rifle and then converted it to piston operation. No issues with the Del-Ton carrier or bolt either. I can't tell any difference, they all work. I would suggest Del-Ton or DPMS for less cost. Then again I have a buddy that does use a lot of Model -1 parts and he's never mentioned any isses with any from them either. Only the carriers with some wonder coating that says no lube, runs forever will be expensive. Any run of the mill semi-auto bolt carrier and bolt will probably do just fine, though you will need to put a little oil / CLP on it to make it run as the carbon builds up on it from shooting.
Thanks Schuetzenman for your input! i looked at the del-ton carriers and was a little reluctant because they seemed to be the bottom of the barrel. no pun intended. my ar is a bit of a mutt. i wanted to see how inexpensively i could build one without going cheap on performance. so far it's a bushy lower with a hogue grip, a model-1 5 position butt, yankee hill flat top upper, 11" wilson combat barrel with a muzzle brake i made (legally attached of course), shorty hand guards, and a flip up rear sight. it's all together just waiting for me to make up my mind.
My suggestion would be a BCM full auto bolt carrier.
It's probably within 20 bucks of any other carrier you buy.
Suit yourself, I gave you da tip of the day. I've been using my Del-Ton upper for 3 years now. There are dozens of others on Gunsnet that have Del-Ton complete uppers and or complete Del-Ton rifles. Nobody has reported any issues with any Del-Ton guns or gun parts. Now reading about an 11" barrel you're using, now those are trouble. Lots of extraction and stuck case problems on shuch short barrels. I hope they got the gas port size right or you're in for a world of problems.Originally Posted by hogmister
Schuetzenman, i meant i looked at the del-ton carriers before. the advice you gave is appreciated believe me. i was only assuming that they were too good to be true when i checked them out before. now that i know there are satisfied customers, i'm not so sceptical. thanks again.
Schuetzenman, now about the 11" barrel. are you referring to the size of the gas port in the barrel? i thought they were all a standard size. i made sure the barrel was clocked straight up and down when tightened so the gas port in the front sight was directly over the port in the barrel. and so the gas tube did not rub the inside of the reciever or lock ring.
Yes I'm talking about the size of the hole in the barrel that lets the gas into the front sight / gas block system and then goes down the stainless gas tube. The original Stoner design for his direct impingment gas system was on a 20" barrel. Anything shorter than that starts raising the pressure in the chamber at time of bolt unlock as the distance the gas has to travel is shorter. This is a chronic problem with 16" / 14" M4 carbine types. Extra power extractor springs and even small urathane O and D ring washers to boost the extractor grip force on the case rim were created to overcome this higher chamber pressure issues. If the chamber gets dirty or you use lacquer cased Russian .223 ammo I've seen rims torn off the case during bolt return. Then it's cleaning rod time to knock out the stuck case. A 10" commando barrel is just more of the same, too early a timing on bolt unlock and case extract. Oh, there are also extended pitgail type gas tubes to delay the gas and unlocking of the bolt group for these short ones. Also an adjustable gas tube is out there but these all cost some serious money. Since you reload you might be able to tailor some rounds to suit the shorty if it gives you trouble.
Years ago when I was first getting into AR15 weapons I had a buddy that was very familiar with them. He built a commando up with a 10" tube and the long silver soldered on flash hider. He could not get that weapon to run for poop. He finally gave up after a year of dicking with it and just went and got a 16" CAR barrel. That one ran right off with no isses.
Last edited by Schuetzenman; 07-15-2011 at 07:06 PM.
Ok, so if the gas port size is smaller the pressure would be higher and bigger would be lower pressure right? or is it a gas volume issue? hence a longer gas tube "fixing" the problem.
yeah, i was trying to be cool and build an XM-177 'esque' carbine. i did read some potential extraction issues with the shorty barrel. my hopes were to curb that with my muzzle brake. hoping that it would bleed off some pressure for me. i researched brake design and built, what i hope is, a very efficient brake. if nothing else i think it looks awesome. that said, form over function is my business! might backfire on me this time.
I worked out a deal on a bolt/carrier assy. i'm trying to get it together to test this weekend. i feel a range report comin on!
IMO the pressure is the pressure. If a round is loaded to 50,000 psi, the size of the gas port hole shouldn't alter the pressure in the tube, only the volume of gas in the tube. A smaller hole IMO is what is needed. That buddy of mine tried opening his up thinking he wasn't getting enough gas, made it far worse. The small hole should make it take longer to get enough gas volume in the tube to pressurize and kick the bolt carrier back to unlock the lugs from the barrel extension. I've often wondered if a vented tube would help over gassed shorties. Stuff I might screw around with some day if I ever go SBR on an AR rifle.
Del Ton.
Face your fear, accept your war.
Gas tubes are cheap enough to fool around with. if i have problems, i'll pick up a few to test some theories on. got a good think goin on an adjustable one. maybe even a chamber or extended shorty gas tube to slow it down.
well as usual nothing went as planned. been working all weekend. no time to shoot. hope to try out the ar next weekend.
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