6x45 AR?

[effendude]

With all this talk about the new 6mm ARC, Grendels and AR type cartridges, I'm reminded of some old timers in the HP/XC game talking about the 6x45. Not sure if the guys built bolt guns or gas guns but it has me thinking why not an AR? I know it lacks the case capacity of the other cartridges, but I've got many 6mm bolt rifles, already in a variety of case capacities. I'm not looking for a 600 yard rifle, just a rifle to plink with, prairie dogs and maybe coyotes up to 3-400 yards. I'd limit bullet weights to 90 grains or less.

Any experiences forum members can share?
Thanks,
Scott

 

[ShaneG.]

I bought a reamer a while back and chambered a take off from my Panda and stuck it on a Savage. Shoots light bullets very well. I have a few more take offs and will machine one down to build an AR...the lower is ready to go I just need to get it done when I get time.

 

[1lnbrdg]

I've got a 1/8 twist AR upper built but haven't taken the time to do load work-up. It's on the agenda to do this week and shoot next week while I'm on furlough.

 

[Kings X]

Common problem with AR 6x45 - have to seat heavy Bullets way down in case. I run 85 Partitions.

 

[HandgunHTR]

I run a 24" Black Hole Weaponry 6X45 barrel on one of my ARs. It shoots the 80 grain Sierra single shot pistol bullets into tiny groups when using AR-Comp.
If you window your mags, you can load them a little longer in order to get some more powder space.

 

[IA_shooter]

Reviving this as I just purchased a new to me 6x45 upper and I'm hoping a few guys have recommendations on a good powder to use for 75-85 grain bullets. I like the 223 wildcats and I used to have a 6x45 upper years ago and wished I had kept it. It did well for me for hogs in TX several years ago but I can't remember for sure the powder I was using but I think it was Varget and I was using 80gr soft points.

 

[22vartarg]

Sierra lists in their manual the following powders for the 6x45:
IMR 4198
IMR 3031
H322
Accurate 2230
Win 748
H335
H4895

 

[1lnbrdg]

IMR 8208 ~25 to 26 grains best velocities and accurate for me.

 

[IA_shooter]

IMR 8208 ~25 to 26 grains best velocities and accurate for me.

That's what I am probably going to go with and I have some on hand thankfully. I just ordered a few hundred Sierra 80gr from Midway to use. That's what I ran in my 6x45 I had several years ago and had great luck with.

 

[Bc'z]

Reviving this as I just purchased a new to me 6x45 upper and I'm hoping a few guys have recommendations on a good powder to use for 75-85 grain bullets. I like the 223 wildcats and I used to have a 6x45 upper years ago and wished I had kept it. It did well for me for hogs in TX several years ago but I can't remember for sure the powder I was using but I think it was Varget and I was using 80gr soft points.

What twist rate

 

[1lnbrdg]

I'm shooting a 1/8 twist 70gr TNT thru 95gr Sierra's single loaded.

IMR 8208 fit the best for everything I tried. CCI 450 primers or Remington SR.

 

[IA_shooter]

What twist rate

It's a 1-8 twist 20" bbl

 

[7887mm08]

IMR 8208 ~25 to 26 grains best velocities and accurate for me.

2nd this (but in a bolt action)

 

[Roy39A]

8208 with 26 to 26.5 grains shoots everything from the 70 grain TNT to the 80 grain Sierra Blitz. 1/8 20" AR. I have killed numerous hogs and coyotes with my 6x45.

 

[JSH]

I never could understand why more AR shooters never played with the 6-223/6x45. I think 80’s and under would function well at mag length.
I have played with this and variations of for a number of years. Always performed over an above what I expected, heard the same from others with bolt guns.
Threw a “budget” 6TCU together, 1-8” twist zero free bore. It thrives on 55-75 grain Vmax and isn’t picky on powders.

 

[Andy Legg]

I never could understand why more AR shooters never played with the 6-223/6x45. I think 80’s and under would function well at mag length.
I have played with this and variations of for a number of years. Always performed over an above what I expected, heard the same from others with bolt guns.
Threw a “budget” 6TCU together, 1-8” twist zero free bore. It thrives on 55-75 grain Vmax and isn’t picky on powders.

Did you ever push any out past mag length? If so....What was the heaviest?

 

[1lnbrdg]

I've shot up to 87gr Hornadys mag legnth but with my chamber they work. I'm my bolt rifle I shoot Sierra's 95gr MK 1/8 twist, very competitive with Palma rifles at the 600 yd line.

 

[Andy Legg]

I'm wanting to try the Nosler 105 RDF over mag lenght single feeding in a 1/8 AR (20").....hoping to get at least 2500 fps.

 

[1lnbrdg]

Let us know how it works. For most chambers that's going to put a whole lotta bullet in the case (throat legnth) taking up room needed for powder.

 

[Andy Legg]

I dummied up a round with one of the 105's and checked it in the barrel. It touches the rifling somewhere between 2.585"-2.590" COAL.

I plan to load the 105 RDF's at 2.560"-2.565" COAL.

Comparing the 85 grain Nosler Partitions(bullet length=0.950") loaded at 2.260"(Mag length) & 105 RDF's (bullet length=1.250").......I believe that I should have about the same available case/powder capacity.

I need it to go at least 2500-2600 fps.

I'll let you know how goes it.