4000fps with 6BR?

[USAPatriot]

Is 4000 fps possible with the 6br? I got there with this rifle when it was a 22" 1:12 .243 using 43.9 of H4895 and Nosler 55's. But this is a 28" 1:10 and the 6BR doesn't have that case capacity. Still, the 6BR mostly does what the .243 will and does it with less, so maybe it's possible. Thoughts? Thanks! -Rod-

 

[Forum Boss]

Darn close is the answer, with the right powder and a long barrel.

Try AA XMR-2015 with Sierra 55gr BlitzKings. We know some guys who are topping 3800 with that load.

QuickLOAD also predicts 3900 fps+,in a 28" bbl) with Winchester 748 and Hodgdon H322. It predicts 3880+ with Hodgdon H335; Ramshot X-terminator; Reloader 10X.

 

[6Dasher]

I got up to around 3850 with the same 55gr Nosler in my 21" 6ppc. A 6BR should be able to do it, question is why?

 

[EdAtts]

How much 322 or 748 does it take to get 3800 fps in a 6 br?

 

[Forum Boss]

How much 322 or 748 does it take to get 3800 fps in a 6 br?

I don't want to print the loads here because they exceed Powder Makers' recommended loads. We're talking 62,000 psi. That's high, but it is a zone where folks with custom actions are operating successfully. 6 PPC shooters normally exceed that by quite a bit.

I ran a model calling for .150" of FB bullet in the neck, with 102% case fill, based on 38.2gr of actual case capacity. The model also assumes you are NOT jamming into the lands. Your case capacity could be more or less. To give you a reference point, Sierra lists a max load of 31.7gr H322 for the 55gr Blitz-King, with a 2.100" overall cartridge length.

 

[USAPatriot]

Darn close is the answer, with the right powder and a long barrel.

Try AA XMR-2015 with Sierra 55gr BlitzKings. We know some guys who are topping 3800 with that load.

QuickLOAD also predicts 3900 fps+,in a 28" bbl) with Winchester 748 and Hodgdon H322. It predicts 3880+ with Hodgdon H335; Ramshot X-terminator; Reloader 10X.

Hmm. LFDW predicts about the same for the H335 but warns it's a high pressure load at over 52k. And it's a 100% density load as well. I might get 4000 in the heat,versus 70 degrees) with H335 but there's an obvious consequence to that too. -Rod-

 

[AlNyhus]

I don't think you'll get to 4,000 fps with the Nosler 55's. My BR predator rifle shoots the Nosler 55's and some special BIB 57's. at 3,800 with a stiff charge of RL7 or AA2230, though. It's my standard winter predator load. 24" 1:14 Lilja 3 groove and a .265 neck chamber. -Al

 

[TominSWNY]

4150 fps with 45 gr bullets

 

[USAPatriot]

Well, I got all my rounds done for the big day with the new stick. On top of the first 30 rounds for break in with 30.0g of Varget I added:

,All of these are also using Nosler 80's. It was just easier for this stage of the game)

7 rounds Varget, 31.5g
7 rounds Benchmark, 28.0g
7 rounds Benchmark, 29.0g
7 rounds Benchmark, 30.0g
7 rounds Benchmark, 31.0g

In addition, ONE round each of N133:
26.0g
27.0g
28.0g
29.0g
30.0g

Basically I decided to see what the chrony was going to show me and if I manage to shoot a decent group along the way, I won't complain. 7 rounds is 2 sighters + 5 for the group. 1 EACH on the N133 is because I'm not quite sure what the short loads of a fast powder are going to do pressure wise so I didn't see a lot of sense in making up more than one for now. If I don't see pressure signs and the velocities are good I can always play with them some more. Hopefully I can get out there sometime this week, but I'm not sure yet. Those 70 rounds should keep me out of trouble for the day. -Rod-

 

[TominSWNY]

32.0 gr of 133 with a 55 b-tip gave me 3600 fps from a 27 inch barrel

36.0 gr of 322 put me close to the 4000 mark

 

[USAPatriot]

I have H322 and H380 available but I tend to use the powders that are more temp reliant I guess. It's a hard habit to break, but I picked it up when I lived in Colorado, where the temps could swing 40-50 degrees in a single day. I'd planned on H4895 but when I went to my powder bin it wasn't there. Either I misplaced it or someone borrowed it. I know I didn't use it up. Grumble. I was scrounging my bullet bin last night and found a 3-4 year old baggie full of Barts 66's. I'll definitely have to give them a whirl. -Rod-

 

[Ackman]

A 6BR and 55's will do amazing things. My 24" Hart barrel shoots very small ragged hole groups at 3777 and again at 3919 with 55's and AA2230 powder.

 

[USAPatriot]

A 6BR and 55's will do amazing things. My 24" Hart barrel shoots very small ragged hole groups at 3777 and again at 3919 with 55's and AA2230 powder.

I've got a lot of 55's, all Noslers. But my bbl is 28" and I've no Alliant powders at all. LFDW shows pressure at anything over about 3500 but when it comes to the 6BR it seems to behave strangely and I don't know that I trust it. If with a given bullet I'm presented with a dozen powders to choose from, the velocity won't change within groups of 4-6 powders. Picking 3031 or N201 yields the exact same results. I never saw that loading for .223 or .243. So I don't know how much I want to trust the software, especially since the gun has still not been tested. -Rod-