AR 15 bolt and carrier?

[ebb]

Does it matter which you use? Are any better than the others? If there are some that are head and shoulders better than the others, will I shoot it enough to tell the difference? What do you use and why?

[M-Tecs]

Not recommending a brand but you have many options for non-Mil Spec bolts and carriers. Once the laws where clarified the heavier M-16 full style auto style carriers verse the semi-auto seems to be the majority of what users prefer for standard usage. The 3-gun speed shooters all want light weight for faster cycle times and less recoil movement. The people wanting to shoot heavier bullets for long range prefer heavier carriers to slow cycle time to allow for higher pressures and easier on brass.

Some more info here.

https://www.pewpewtactical.com/best-...carrier-group/

https://www.recoilweb.com/best-ar-15...ps-176713.html

https://thegunzone.com/best-ar-15-bc...carrier-group/

https://www.wingtactical.com/best-ra...carrier-group/

I do prefer Yong Manufacturing NM bolts for heavy bullets and BCM for general usage but the truth be told I've never had any issues with the generic cheap bolts and carriers.

If you're going to shoot it a lot, I do recommend upgrading to the McFarland 1-piece Gas Rings. https://www.bing.com/search?q=mcfarl...QBRE&sp=1&lq=0

https://vtsupply-com.3dcartstores.co...R-_p_5938.html

[243winxb]

Buy the same brand/manufacture of bolt & barrel. This helps get a correct chamber headspacing/Head clearance.

Avoid heat treated parts. If not done correctly, bad things may happen.

i used a factory produced M16A1 carbine.

photo of 204 Ruger. NOT RUGER PARTS/RIFLE.

[jdgabbard]

My advice, stay away from the cheaper budget BCGs with fancy coatings. They look nice, but you will generally get what you pay for. The BCG is the bolt, the carrier, part of the gas port, and the piston all in one. It's a very critical part for proper operation of the rifle. You ideally want one that is MPI scanned and Phosphated and chromed. I've tried the others, they just don't compare most of the time.

[M-Tecs]

Buy the same brand/manufacture of bolt & barrel. This helps get a correct chamber headspacing/Head clearance.

Avoid heat treated parts. If not done correctly, bad things may happen.

i used a factory produced M16A1 carbine.

photo of 204 Ruger. NOT RUGER PARTS/RIFLE.

Both the bolt and bolt carrier are heat treated and they have very specific specifications for the heat treatment for that specific material. A un heat-treated bolt would be a very serious safety concern. Since the M-16 was milspec'ed improved materials and processes have been developed. At a minimum those materials/processes will meet or exceed the original Milspec.

The original M-16 Milspec's specified a total tolerance of .003 from the back of the recoil lugs to the bolt face. That is the maximum allowed. I've inspected several hundred AR15 and M-16 bolts. While the total tolerance is .003" the worst I've ever found was about .0015" and normally under .001". While out of tolerance parts happen and it's always recommended to check headspace after assembly it comes down to are the barrel extension and bolt within tolerance? Brand of manufacture does not change the tolerances.

Some good discussion here but the first post is incorrect on the plus or minus tolerance. The correct info is .156" -.003" https://www.ar15.com/forums/AR-15/Me...s-/118-759869/

Actual Milspec prints here. https://ia600406.us.archive.org/32/i...0schematic.pdf

[nekshot]

I believe what you want the gun for really dictates the quality. I stay away from cheap but do not pay top dollar either. We do not shoot many rounds a year. I personally only shoot mabe 30 rounds a gun in a year. I have had times of a couple hundred per gun as I work up loads but when I find the sweet spot I am done. Too many guns to shoot I guess. I know I do usually go thru a thousand or two of primers a year. I have never had a failure with any of the ar’s I built.

[Scorpion8]

Buy the same brand/manufacture of bolt & barrel. This helps get a correct chamber headspacing/Head clearance.

Not entirely true once the military went to multiple vendors (Colt, Bushmaster, etc) the parts were all "milspec" to be compatible. It is rare to find an AR bolt-barrel combo that headspaces wrong in my experience. In fact, I've never encountered one.

[M-Tecs]

Not entirely true once the military went to multiple vendors (Colt, Bushmaster, etc) the parts were all "milspec" to be compatible. It is rare to find an AR bolt-barrel combo that headspaces wrong in my experience. In fact, I've never encountered one.

When AR15's started to be an accuracy rifle in the early 90's all the custom barrel makers required you send in the bolt of purchase a bolt from them to ensure proper headspace if they chambered it. Most, if not all of them, dropped that requirement since it was a non-issue with AR bolts and barrel extensions. That is not as true with the AR10 design since the civilian AR 10's were around before the military adopted the M110.

[243winxb]

https://www.thehighroad.org/index.ph...-issue.824277/

And https://www.thehighroad.org/index.ph...-space.827435/

.

[243winxb]

Not entirely true once the military went to multiple vendors (Colt, Bushmaster, etc) the parts were all "milspec" to be compatible. It is rare to find an AR bolt-barrel combo that headspaces wrong in my experience. In fact, I've never encountered one.

See 2 examples. With many manufacturers of AR15 5.56/223 parts, i would check with headspace gauges. Unless your feeling lucky.

[Shiloh]

Black Friday
Economical

https://palmettostatearmory.com/psa-...516446953.html

Shiloh

[Gtek]

Checking the headspace is a VERY GOOD idea on a new build or buy even if they are from the same place. Oh the stuff I have seen over the years, especially ten to twenty years ago when everybody was in the game. Once you correctly do it or have it done you can hang your head behind that 52-62K PSI with a little more confidence!