AR10 are cool. Can be a bit heavy, but not so much that it's a problem if you build them right. I make my own AR10 barrels from blanks and getting a rifle at about 10 pound's loaded, with a sling and a scope is not all that hard to do. In fact I can make them even lighter is need be, but not by a lot without doubling the cost.

I made one, a 308, for a 12 year old girl for Christmas 2 years ago and it's her pride and joy. She is quite a good shot with it too, and her whole family are hunters. She didn't want to get kicked so I put a large muzzle break on it with warning to not fire it without her ears covered. But just about 2 months ago her dad took her out shooting and she put 10 rounds into a group on a paper target at 100 yards that were all in the size of a small chicken egg,(about 1-5/8") and that from a field prone position, laying on her belly shooting over her school book-pack. She does well on deer and antelope and this season she's going for elk. Her rifle is field ready at 9 pounds 7 Oz.

I just finished one in 338 Federal yesterday and my friend is coming in about 1 hour to pick it up.

In my years of gunsmithing I have made "10s" in 243, 260, 6.5 CM, 7-08, 308, 338, Fed and 358 Winchester.

In the last 25 years or so the 2 most popular calibers were #1 the 308 Winchester (by at least 3 times) and next the 7-08.

The 260 was ok but when the 6.5 CM came out the 260 simply disappeared from AR10 orders
The CM was designed from the start to fit in the NATO length mags and still take the longest and heaviest VLD bullets, which it does wonderfully. The 260 will actually beat the 6.5 CM if the magazine and throat of the chamber will allow the use of the same long bullets, (some bolt actions are set up that way) but that can't happen in an AR 10 mag.
These days the 6.5 CM and the 7-08 are about a neck and neck tie for the second most popular caliber ordered in custom AR10s. But the 308 is still in the #1 spot, and that by a considerable margin.

I made one for myself a while back and I did it in the 308 and next I made a complete upper in 358 Winchester so I can swap it back and forth. But I debated back and forth for quite some time about making a 338 Federal instead. But I am happy with my 358.
One thing I do fairly often is make custom AR10 style barrels for other builders. I set them up for the length of gas tube they want and head-space them for a bolt that either comes with the barrel, or I set the headspace to the bolt they send to me. In that way anyone that can do "kitchen table builds" can have an AR10 in a "custom caliber" and in any length and twist available for that bore size. The rest of the build is simply like any assembly job on any AR.

Last edited by szihn; 06/30/21.