6 dasher help

[Estes640]

I've got a new dasher comin to me, 20rds fired on it, and I've got 100 pcs of hydroformed brass coming as well. Is there any need to fireform the hydroformed brass or can I load an ocw and shoot it up to full power loads?

Any advice will be helpful!

 

[culater]

Ask that question on 6mmbr.com you 'll get your answer

 

[ZiaHunter]

Probably best to fire form the cases first since the hydroformed cases will have less capacity which will have a higher pressure than fire formed cases. When fire forming I step down the charge weight.

 

[Estes640]

Thanks guys. Next question is, what are your favorite fire forming loads?

 

[ZiaHunter]

I use 30 gr of Varget.

 

[Estes640]

I use 30 gr of Varget.

With a 105 jammed?

 

[Sheldon N]

Most guys say that they can run hydroformed brass at pretty much full pressure loads and get good accuracy. Classic Dasher load of low to mid 32 grains of varget behind a 105 jumped. Check your shoulder bump to make sure cases fit your gun's chamber, bump the shoulder a tiny bit if they are too big.

However, with only 20 rounds on the barrel with and 100 hydroformed brass, I'd probably shoot through the lot once before starting load development. No so much for brass's sake, but rather for consistency. Barrel will speed somewhere in the first 100 rounds, so better to get everthing stabilized first, then worry about finding the ideal load.

 

[ZiaHunter]

With 31 gr of Varget I was getting flattened primers when fire forming hydroformed brass so I backed off the charge. I am not jamming but running about .005 off the lands. I did experience very good accuracy while fire forming but experienced better groups with fire formed brass.

5 Shot group at 100 with fire formed brass 33 gr of Varget behind 105 Bergers.

 

[MakeSawdust]

Not Dasher, but I hydroform 243AI and get similar accuracy as with fireformed brass. I hydroform slightly long and then FL size to push shoulders back. This sharpens the radius on the shoulder that guys talk about from hydroforming. I run the exact same load regardless.

 

[ultrarunner7]

30 gr of Varget seated 30 thou long jammed in the lands. 400 pcs of lapua brass with only 4 pcs splitting.