6br primer fire hole

[Perk]

I bought some Alpha 6br brass and they have a .080 hole in the primer cup. Will this make my loads different. Will it affect the pressure in the round? Thanks Perk

 

[Bill Norris]

I bought some Alpha 6br brass and they have a .080 hole in the primer cup. Will this make my loads different. Will it affect the pressure in the round? Thanks Perk

Alpha's claim is the larger flash holes produce better ignition. I'm not sold on the idea.

 

[fkimble@charter.net]

You got the brass and the gun. Load up 5 and see how it goes. If your load is on the warm size, drop it a couple little to begin with. Bet it works just fine.

Frank

 

[LCazador]

That bigger flash hole is going affect ignition, pressure, ES, point of impact, group size, etc. Start from scratch with a middle of the road powder charge with bullet seated into the lands so you that your brass fireforms correctly. Make a note of the head diameter just forward of the extractor groove before firing. Take that same measurement after fireforming. Hopefully this dimension has not expanded more than .0005". If all is well with the head diameter, fireform 20 pieces and then test three powders. If you don't have the luxury of three powders that will work for the powder test. Test two powders. Testing with just one powder may not reveal the best load. Always fireform first and then test. Take a headspace measurement of those firefomed cases and note that measurement then bump .002". Now you're ready to test those old loads or you can start anew. I would start over if my old cases had the smaller flash hole. Nothing says the bigger flash hole can't work out to deliver better results.

 

[Clancy]

Just switching manufacturers is cause enough to back off and rework. I have alpha BR but haven’t messed with it yet. Alpha BRA took less powder for the same velocity.

So, yes, it’ll make your load different, whether it was because of the small flash hole or not I don’t know, but I doubt it. Maybe a small amount, but certainly mostly because the Alpha is thicker and has less capacity.

It’s been pounded and theorized for years, but the only time I’ve seen it tested in a controlled environment the small flash hole outperformed the large— BUT, it was by an immeasurable margin and was proven to be completely insignificant for the guy’s application. No joke, I think it the difference in ES and SD between the two (not velocity just measured of ES and SD) would not have amounted to a single click until like 1400 yards in his 6x47L.

 

[Perk]

Thanks all for the information. I will start anew with the Alpha brass. Perk

 

[Kracken McGraw]

Is the .080 hole the standard small hole measurement like on the 223 Remington?

 

[Perk]

The flash hole on 223 is about .062 the one on Alpha 6br is .080.

 

[Kracken McGraw]

Ya might want to read this thread regarding Alpha brass. I think they did OK in @GlennK set up.

Alpha 6BRA brass

Shawn there are NO GUARD RAILS, at one point he wanted to send scientists in to see if my underwear were to tight to make good test bullets!!!

forum.accurateshooter.com

I’m glad you posted that, I was thinking one of you guys up there we’re having a lot of success with the Alpha brass!

 

[newbieshooter]

Ya might want to read this thread regarding Alpha brass. I think they did OK in @GlennK set up.

Alpha 6BRA brass

Shawn there are NO GUARD RAILS, at one point he wanted to send scientists in to see if my underwear were to tight to make good test bullets!!!

forum.accurateshooter.com

:

Glenn kicked ass all season, plain and simple.

...also 2021:

Sunday Gunday: Glenn Kulzer Sets 8 1000-Yard Records in 2021 « Daily Bulletin

Kulzer Sets Eight New IBS 1000-Yard IBS Benchrest Records with 6 BRA Rifle Report by Alex Wheeler 2021 was a banner year for 1000-yard Benchrest. Glenn Kulzer of Dillon, Montana had a season that will go down in history. Glenn set eight IBS records in 2021 at the Deep Creek range in Missoula...

bulletin.accurateshooter.com