"National match" bolt carriers.... are they "commercial" or "mil spec" diameter?

[gene]

I am buying a National match bolt carrier from Young Manufacturing... Does anyone know if that is going to be a mil spec or a commercial diameter carrier????

Thanks

Gene

[pinzgauer]

I've not ever heard of bolt carriers being different diameters, the "mil-spec vs commercial" diameter is normally with receiver extensions/buffer tubes.

The NM carriers are normally heavier, but for some reason I remember some were super light (faster cycle??) which you would not want for grendel.

I checked out the Young chrome NM's for a build but ultimately just elected for a good M-16 carrier. (which is also heavier)

[Drifter]

No such differentiation regarding BCG's. NM's might be made to tighter tolerances and closer fit, but that's it.

[LRRPF52]

There was a time when they were making carriers with a slightly larger diameter to the raceways, to fit the BCG tighter and more concentric with the bore. Several customers had problems with reliability due to increased friction in the receiver. My understanding is that they had to go back to a standard diameter, but I haven't heard that from the horse's mouth. I've ordered slickside chrome bolt carriers from them for retro projects, and they are fine. I would just use an M16 carrier with the Grendel.

[rasp65]

I am buying a National match bolt carrier from Young Manufacturing... Does anyone know if that is going to be a mil spec or a commercial diameter carrier????

Thanks

Gene

Gene I think you are confusing the buffer tube for CAR type stocks.

[LRRPF52]

Gene I think you are confusing the buffer tube for CAR type stocks.

Nope. Young's makes NM bolt carriers that have had some differences in diameter in the past...read above. This isn't a mistaken question about extension tube diameters, since nobody makes a National Match extension tube for competition guns, as they use full-length stocks anyway in high-power and DCM.

[pinzgauer]

There was a time when they were making carriers with a slightly larger diameter to the raceways, to fit the BCG tighter and more concentric with the bore.

Thats not something I've seen in their offering recently. They do have one with more surface area on the front of the BCG in an attempt to decrease play, etc. It's also heavier. They also have polished M-16 carriers, as well as "light" carriers which decrease cycle time and would be in appropriate for Grendels.

I considered getting one just for ease of cleaning, but backed away just due to cost and availability.