New build caliber options

[RobertFL]

Things seem to be getting better.. Other than the barrel....I had no problem finding parts for this 350L build. Even found some winchester 160 defender ammo to try..

[MISportsman]

I have pretty much decided on the 6.8spc. Looking into barrels I'm torn between the bison arms 18" and the stag arms 20". Any thoughts on either?

[grayfox]

there might be some opinions on the 6.8 forum.
I left the spc in the dust-bin years ago for the grendel and have not looked back.
good luck, you'll need it.

[MISportsman]

I thought about building a 2nd grendel, but then decided to go with something different this time.

[Oso Polaris]

300HAMR is easy answer, especially if you already have a 6.5 Grendel.

1) Accurate & Reliable 300-400 yard hunting cartridge with no pressure issues or concerns about bolt failure.
2) Velocities either match or exceed 6.5 Grendel for same bullet weights.
3) Inexpensive to Reload;
a) easy conversion/forming 300HAMR cases from .223/5.56 cases.
b) huge selection of projectiles: uses popular .308 bullets from 110gr - 150gr. Due to the 6.5 premium and the .308 production volume discount, .308 bullets are less expensive than 6.5 bullets.
4) Proven terminal effect on wildlife. Bill Wilson has personally tested the cartridge and ammunition (various bullets) over past 3-4 years and has racked up a substantial kill list in excess of 3,000 hogs!!!

[MISportsman]

I really like the performance of the .300 ham'r, the only reason it's not a top choice is ammo availability. If it was easier to get I'd build one in a hurry.

[Oso Polaris]

Easy to reload.

Wilson is selling ammo directly at reasonable (not inflated panic premiums). Scroll down the page past the the warning notice... https://shopwilsoncombat.com/300-HAMR-Am...ucts/1070/
Sig Sauer is making ammunition for it as well.


Speers, Hornady and Lehigh Defense are modifying or custom tailoring bullets specifically for the 300HAMR. My sense is that several major gunmakers were prepared to launch rifles chambered in this caliber, but the market chaos from the pandemic postponed everyone's normal business plans.

[MISportsman]

I wish I could find all the components and a good source for ammo, I'd love to build a 9x39! The possibilities of this cartridge look to be awesome!

[tdbru]

MIS,
9x39 could just as easy be 0.358"x39 too. Might be just as easy to get bbls. Who knows? If you're contemplating Subsonic thumper without throwing 45 caliber amounts of Pb downrange, the 9x39 or 358x39 would give you access to bullets up to 310 gr. solids. you'd need a 1-10 twist for that long of a bullet at subsonic speeds. Could plink, most likely with pistol bullets. would have more zip than the 350 Legend if you need more zip. If you shoot/reload a lot of 9mm Luger the 9x39might for sure be interesting. Shoot 9mm 147s a bunch faster if wanted. Or go really heavy for subsonic. or for varmints a 110gr 0.357" XTP at max velocity.

I still think the 6.5 Grendel has the better balance, but if you're looking for something very different the 9x39 may prove quite interesting.

and if the very inexpensive 7.62x39 ammo ever comes back into the country, well having an upper that runs it makes plinking/new shooter orientation and practice much less ammo expensive.

just some thoughts.

I had a new shooter out today with a mini howa in 7.62x39 for CF rifle orientation and practice. feeding it the lower cost steel Wolf 7.62x39 plinking ammo enabled more shooting time and rifle orientation for the newbie. and saved my brass 6.5 Grendel ammo for more serious applications, like hunting.

-tdbru

[ETEX HUNTER]

IMO, you cant go wrong with any build or caliber.

[drykilned]

Sorry bout this being so much late but I just rad the thread. I have built 7 7.62x39 ARs in the last few months just for me and my kids. All have BCA barrels and several different BCGs, whatever I could get my hands on. I still have my 65 grendels, but components for ammo got SCARCE and I could buy 7.62x39 124 gr and 154 gr SP in bulk for my deer hunting and coyotes. My ARs in this caliber all shoot close to MOA out to 150 yds (124gr) and 200 yards (150 gr Hornady bullets in wolf/tul cases with 154 gr sp pulled and replaced with .308 Hornady). I found that .308 Nosler 125gr Ballistic Tips also shot MOA when 124 gr sp wolf or 124 gr norma FMJ were pulled and .308 125 gr BT replaced. I use the lee factory crimp die and the .308 dia bullets work very well. Have not chrono'd yet due to not wanting to waste bullets. What I did do was use gallon milk jugs filled with water at 100, 150 and 200 yds. The wolf/tul 124 gr sp quit exploding the jugs at 150yds, 125 gr nosler quit at 150 yds, 154 gr wolf/tul quit at 150 yds. The 150 gr hornadys still exploded jugs at 200 yards with 1008 pounds energy by nikons ballistics chart. I am going next to 135 .308 FXT in wolf/tul 154 gr pulled cases. All barrels were 16" hvy. 1 on hand assembled Anderson lower with Velocity 3.5lb trigger Anderson upper receiver. All the others with Anderson upper receivers and Omega Poly lowers with Mil-spec tubes for weight reduction. LOVE'EM!!!

[pashiner]

based on what you've already got, I'd suggest .300BLK. it's a tinkerer's/reloader's dream. Factory ammo availability is as good or better than Grendel, and no more expensive. You can use nearly any .30 spitzer bullet ever made, converting brass from .223/5.56 is pretty straightforward, brass lasts forever, and it's not powder thirsty at all. I do some bullet casting, and the blackout is ideal for plain lead...even in an 8"twist. with a 110 gn load, you can get 2300+fps from a 16"barrel. Short barrels don't lose much velocity if you'd rather do an sbr. You can duplicate 7.62x39 ballistics with a 125, or slow it down suppressed with 250 grain thumpers without even monkeying with your gas system or buffer.

It's the most versatile, cheapest to shoot cartridge that I reload for.

my favorite current load is a powder coated 230 grain boat tail spitzer bullet from the Lee .309-230-5r mold over 7.3-7.4 grains of lilgun.
size to .309 after coating, and seat to the crimp groove. The most expensive part is the primer! these are pretty darn quiet from a 16" barrel at 1100fps, even unsuppressed.
with a can on, you hear the hammer drop and the impact on target. With the insane BC of that bullet (.688 G1), it retains good energy WAY TF out there.