I looked for any recent threads on this discussion and didn't find any, so bear with me if this is a repeat of another thread. I've got .223/5.56 covered and I'm thinking about what I want to do next. I've listed some options in the poll above, but that is certainly not an exhaustive list, just the ones that seem to be more common among the articles I've read and people I've talked to. The question is based on using a standard AR15 multi-cal lower. One thing I know is that the 7.62x39 may not be a good option in a standard AR lower, but that's all I have on hand at the moment, so I'm leaving it on the list. I'm leaning toward the 6.5 Grendel based on what I've read about it's performance out to long ranges over some of the other choices. I don't have any long range setups at the moment and it sounds like a good one to use for long-range fun, especially if you do your own hand loads. I'm not a hunter, so this would be strictly for learning more about long range shooting. I understand these cartridges can keep going well out to 1,000+ yards, which seems pretty impressive to me. I also understand it can be difficult to find ammo. My second choice is a 9mm, just for cheap fun. Third, I would love to do a 7.62x39, but from my research, it looks like it's best if you get a lower that will specifically work with standard AK mags, and it looks like those are limited choices at best at the moment. Maybe 5.45x39 would be a better choice. .300 BLK sounds interesting, but I understand it's ideal for suppressed applications, and at this time, I'm not planning on running a suppressed setup. So I'm curious, if you were looking at your next AR15 based build, what would you choose and why?
458 SOCOM....thought about 300blk but thought if I am going for a glorified pistol round I'm going big, don't care about suppressing......plus I reload, and cast next would be 10MM auto....aside from the blow back Oly. Quarter 10 is on the cusp of figuring out a DI 10mm for the public 6.5 G......I participate in 600y shoots on occasion
300blk IF I wanted a shorter then 16" barrel as that's what it was designed for. Plus the magazines and bolt are all the same. Didn't see it listed but the 25-45 sharps are of interest to me for the same above reasons except for a longer barrel and then hunting would be an option. 9mm sounds fun but need specific to that caliber parts and reliability seems to be an issue.
Why do you want it? My 9MM AR's are some of the most fun to shoot but if the goal is punching holes in paper at 400 yards then obviously not the ticket. I have not had any reliability issues with mine through thousands of rounds. At .16/rd VS closer to .30 for .223 I can do a lot more plinking with the 9MM and they are just plain fun. Now if you actually intend to shoot something with it other than steel or paper that is another matter. That 6.5 sounds like a capable round but not a range toy. It would only be practical if long range accuracy or taking down game was a goal. I like the idea of the 25-45 Sharps simply because its just a barrel. You could have both it and a 5.56 for the cost of a barrel swap. If it was about having a bit more take down power I think that is the way I would go simply because its cheap and easy and if I got bored with it you could always dump the barrel and refit with a 5.56.
I recently picked up a 9mm and have the 7.62x39 next on list. The .50 Beowulf is also one that is interesting, a little more so than the .458 due the straight wall case makes for simpler reloading. I also like the 6.5 Grendel for the same reasons you mentioned above but realistically I will probably not be going beyond the 7.62x39 in the AR15 body for quite a while.
I kind of stated my reasons in the OP, but I was just more curious about other people's opinions for themselves rather than looking just for myself. I find it interesting why people choose particular calibers for particular reasons. Since I don't hunt, knockdown power isn't a huge concern - but you never know, it could be something I take up some day. For me, a 9mm would really just be a fun gun. I am a fan of pistol caliber carbines, but I don't have anything in an AR platform. 9mm is cheap to buy/reload and shoot, so likely it would be 100 yards or less. I read your thread on your 9mm build a while ago and it helped pique my interest in 9mm AR's I haven't looked into the 25-45 Sharps, and since @Joe13 mentioned it too, I may need to take a closer look. It's a round I don't know much about. Keep the opinions coming folks. I love hearing the why's and what's of the various choices. And again, I'm not necessarily looking for a specific recommendation for myself, just interested in what calibers get your interest.
I like this guys channel - not super detailed but light watching and should help give you an idea on the 25 45.
I've seen his videos before, but I keep forgetting to go back to his channel. I'll be sure to check it out. And apparently there is a new 25-45 Sharps round announced at SHOT show (posted on another thread) - apparently good for both hogs and bear. Even as a non-hunter that sounds like something I want to know more about:
I should mention too that I'm thinking of doing the 9mm as a pistol build. Again, all for fun, and I can always change it to a rifle later, so long as I don't create an SBR in the process.
Personally, I've been thinking of doing two SBRs, one in 6.8 SPC and one in .300 BLK. One rifle in .458 SOCOM just to have one.
if your going to get into freaky wildcat reloader rounds like the Sharps , don't forget the .277 Wolverine