Thank you free.. So If I am understanding what you have written you can use the ar15 platform to make interchangable rifles in 204, 223, 221, 6.5, 50 beowulf type calibers and then the ar10 lower can make rifles in 338 Federal, 308, 7-08, 260 Rem, 6.5 Creedmoor, and 243 type calibers. Thank you for the info it really opened my eyes.. I like the potential. {/QUOTE]
ARs are tinkertoys for gun nuts.
As to the differences between an AR-10 and AR-15, the AR-10 is about 1 lb heavier, 1 inch longer, and has a bolt which can handle the thrust of
a typical magnum. An AR-15 can take about half the bolt thrust of an AR-10, though some companies offer modified bolts and barrel extensions to work at higher pressures or with larger case diameters. That and the barrel the only parts of either rifle which is directly affected by chamber pressure.
Once you start assembling them it' becomes addictive and (for the most part) very easy. I have AR-15s in the calibers you mention above plus 17 Remington, 5.7x28 FN, 6mmPPC, 300/221fireball 6.8 SPC, 40S&W, and 458 Socom. Also AR-10s (DPMS LR-XXX) in all you show above except 7mm-08 and 6.5 Creedmoor. I also have one in 300 SAUM. I dont' think the 7mm-08 is factory from DPMS but several companies (Krieger in particular) sell excellent LR(xx) barrels. Olympic Arms offers AR-15s in 223,243, and 257WSSM. And i just ordered a 410 shotgun upper for an AR-15. Got to have something for quail huning ;-)
You'll quickly get over the idea of swapping uppers on one lower. There are so many stock and buuffer options it will make your head swim. I just put a separate lower on each upper with a suitable stock, trigger, and buffer. Otherwise it's too confusing. AR-s also can be made as pistols. A 50 Beowulf pistol is fun to shoot, especially when there are 50 AE Desert Eagle owners watching. Need a pistol for hunting hogs?
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