Pistol Caliber Uppers

[Jack Kardic]

I'd like to get a pistol caliber upper so I can feed the same ammo to my primary and secondary. I sold my good reloading equipment when I moved to a smaller place and it's now a pain to switch loads. I''m leaning towards 10mm but I haven't made up my mind yet and I'm open to suggestions from those who have experience running pistol caliber AR's.

[browcs]

My very small take on pistol uppers is the prevalent caliber is 9mm, so you will probably find more in the way of uppers from companies like Rock River Arms (http://www.brownells.com/.aspx/pid=23064/Product/AR-15-9mm-UPPER-RECEIVER-ASSEMBLY), CMMG (http://www.midwayusa.com/product/881219/cmmg-ar-15-m4-le-a3-flat-top-upper-assembly-9mm-luger-1-in-10-twist-16-barrel-wasp-melonite-finished-chrome-moly-matte-with-m4-handguards-a2-front-sight-flash-hider-pre-ban), and Olympic Arms (http://www.olyarms.com/index.php?page=shop.product_details&flypage=flypage.pbv.v8.tpl&product_id=100&category_id=76&option=com_virtuemart&Itemid=5). Add to the fact that as you probably know, reloading components for 9mm are cheaper than most others, especially over the 10mm which I reload.

The only maker of a 10mm AR upper is Olympic Arms; that or they are best known maker of that caliber.

Curious, what do you plan on using it for? That will help any experienced pistol upper users on this site giving you advice.

[Jack Kardic]

I also reload 10mm, and decided on that because it matches one of my handguns. I don't consider 9mm suitable for more than target events and small game and I want it to be more general-purpose than that. I would have chosen .45 ACP, but in a 16" barrel it actually ends up losing velocity. 10mm hits as hard and manages to gain at least a little bit from the barrel length. I'm expecting my maximum effective range to be about 150m, and that's fine with me.

As far as application, if it proves to be reliable it will serve a home defense role. If it's less than excellent in reliability, it'll be used for plinking and hunting thin-skinned medium game in densely forested areas.

[Stickman]

I don't consider 9mm suitable for more than target events and small game and I want it to be more general-purpose than that.

You could make that same argument against any pistol round, including the 10mm. If you are looking at benefits by switching to an AR15 version of the 10mm for the reason of having more ammo available, I find the logic flawed. My reason is that you are able to find 9 or 45 in much much higher quantities than the 10mm. More ammo to me always means more availability if I'm on the move. If I'm not on the move, I'm stupid for not having stock piled more real rifle ammo....

Just a counter thought, I've got nothing against subcal ARs.

[rob_s]

Rather than trying to do two things poorly with a 16" sub gun (is that an oxymoron?) I'd go with a quality, basic, 5.56 gun and a .22 upper for plinking/training/ whatever.

I don't know anyone who's tried it that found the idea of the same ammo for rifle and pistol to be worthwhile.

[UWone77]

Rather than trying to do two things poorly with a 16" sub gun (is that an oxymoron?) I'd go with a quality, basic, 5.56 gun and a .22 upper for plinking/training/ whatever.

I don't know anyone who's tried it that found the idea of the same ammo for rifle and pistol to be worthwhile.

Rob, I'm glad you're still posting on boards. Always enjoyed your tough love posts on m4c. Hope you hang out here a bit more.

[WarriorArms]

Other than a 9mm, the only other pistol caliber AR I have built was in .357sig. It was a hot round out of a pistol and an even hotter round out of a 16" barrel. At the time, the ammo wasn't very abundant for it, now it is. I got rid of it ...wish I wouldn't have, but I'm too cheap to build myself another one.

[Jack Kardic]

@Stick - It's not commercial ammo availability, it's personal. I load 10mm in 3 - 5k lots and I don't like loading rifle ammo.

@rob_s - I've got a quality 7.62 for my rifle needs. I just want a pistol caliber carbine for, well, mostly because I want one.

I'm not expecting some kind of crazy miracle with this build. I don't think I have unreasonable expectations. I just want a PCC to do PCC things, like perform terminally about the same as a pistol, but be able to reliably hit things a bit farther away. The feedback I was hoping for was more of a "manufacturer x may have difficulty fitting certain lowers" or "manufacturer y has a reputation for poor customer service" etc.