6x45 what the heavies useable bullet

[mao0720]

What is the heaviest useable bullet for a 6x45 seated at mag length, and waht velocity could I expect out of it? Thanks in advance!

Mason

 

[Kermit in Va.]

What twist bbl have you got ???


Kermit

 

[mao0720]

I don't yet, but probably 9 twist. I'm more concerned about bullet length and fitting in a magazine for an AR15.

 

[krummarine]

I am having a 6x45 built on a Rem 700 SA and a 22" sporter weight Benchmark barrel in 9 twist. All of my research so far tells me I am good for 85-90 gr bullets. If anyone else here has more experience with this round, I'd appreciate this info as well.

 

[Ian]

My 21" 9-twist Krieger 4-groove really likes the 95gr. SMK and VLD.

 

[mao0720]

Ian, is that in an AR or is that a bolt gun?

 

[Ian]

Sorry - I missed the AR mag length part of your Q... Yeah, mine is a bolt gun.

 

[johnu]

I've gotten good accuracy with 95g bullets out of my 1:9 twist AR - sorry, never chrono'ed the loads. Any longer than that and you will be losing too much case capacity. The Accurate powder website has some load data that will give you some idea of the velocities achievable with different bullets (albeit with Accurate and Western powders and a 24" barrel.)

John

 

[mao0720]

Thanks John. I think If I can run the 87gr V-max at about 2800 FPS out of a 24" AR then Ill go with this build. If not then Ill look to either keep it simple with a 223 and 77gr scenars or go all out and do a 6mmAR with 95gr Bergers or SMKs.

 

[johnu]

Keep in mind that the heavier 6mm bullet will carry its energy further down range, so even if you can't get 2800fps it would still be better for hunting game larger than varmints. I suspect that, based on its performance, the 6x45 may be a bit more efficient than its .223 parent. Also, you may find that it is easier to tune than some of the hotter 6mm AR wildcats.

John

 

[msalm]

I've built a couple of those on AR's and we've stayed in the 80-85gr bullet. The 85gr Sierra HPBT Gameking works good on whitetails ;D.

 

[gemihur]

I'm using 87 gr. bullets seated to OAL for AR with great results in my contender

 

[Dusty Stevens]

Im the oddball here i guess. Most folks ive built em for use their oddball 65-68gr br bullets and we always used 14tw old br barrels. Mine is on a model seven, 20”#2 barrel, i use oddball ppc powder and old br bullets. My current bag o cartridges is some 68gr barts ultra, h322 and once fired LC brass. Its a killing machine- deer, crows, coyotes, etc- itll git em all and you can watch it happen in the scope

 

[gemihur]

The caliber lends itself to varmint shooting but qualifies as the legal minimum in this state for big game.

 

[JSH]

A 6x45/6TCU fan myself. It will be interesting to see if the 6ARC comes along well. I think there has been a market void for a long time on a factory offered mid size case.
I myself prefer 55-75 grain bullets. The old Speer Hot Core worked well on white tails for me, 80 grain.