Berger 185 BT LR - Starting & Max Load?

[CAU]

My F/TR mid range prone load with the 185 Berger LR is 42.3 grains of Varget for 2,565 fps out of a 28" Broughton 1-10" twist. I'm not sure how this load would hold up at 1,000 but its great at 600. The load shows no pressure signs in any temp I've shot it from high 90's to mid 40's. I use Lapua brass and Fed 210M primers.

Chris

 

[DennisH]

I have a box that I will be working with for my new Brux barrelled 700. I am going to start at 42 for my ladder and go up in .2 grains, up to 44.

First, I agree with the above and I started a ladder test yesterday with my new 27" 308-10 twist bull barrel, shooting 185 and 190grn Berger's!

The below is for my two 308's ONLY, You need to start a ladder test I started out at 42.0 grains!

My chrono was not working yesterday, I can't give details.

Through my ladder test, my load is going to be somewhere between 42.9 and 43.4 grns varget shooting 185 Bergers. I had some .030 off the lands, and some .010 in the lands. The ones .030 off were doing pretty good! I am going to try some .050 off just to see! 43.5grns Varget did not show any pressure signs in MY gun!

I have a 10 twist and a 12 twist. My 12 twist likes 190 Bergers, 43.5 Varget, .010 in the lands!

The 10 twist is going to take a little less powder and for some reason likes 185's better (than 190's)!

Just a side note: My new 10 twist barrel was holding sub .300 groups (100yds) shooting 155.5 Bergers with 44.9grns Varget. I was actually surprise. I was breaking in the barrel and was using some surplus ammo to do so. I was shock to see the groups they were shooting (3 seperate 5 shot sets).

 

[thefitter]

...My usual load development method is to work up to SAAMI maximum with instrumentation...

Would you please explain this process? Thanks

 

[GermanS1]

I use the Oehler 43 system which uses strain gauges on the barrel to measure pressure. The system elongs to a friend and I don't get to use it quite as often as I'd like, but all the data collected from it is in a big binder that I keep and it is incredibly useful.

 

[thefitter]

I use the Oehler 43 system which uses strain gauges on the barrel to measure pressure. The system elongs to a friend and I don't get to use it quite as often as I'd like, but all the data collected from it is in a big binder that I keep and it is incredibly useful.

So that is your primary judge of pressure? How often does your data correspond with published data from powder manufacturers?

The reason I ask is I have been getting some conflicting opinions on exceeding book max and reading pressure signs. Some people believe that bolt lift, primers and extractor swipes are not good indicators of pressure. And others believe that anyone that deviates above book max is crazy.

I don't mind being crazy as long as I'm safe.

Thanks

 

[GermanS1]

I generally have found that the data in the Sierra book for .308 and .30-06 is very accurate as to maximum pressure. The Lapua data for 6BR is also very accurate. I don't mean to imply that there is inaccurate data elsewhere, these are simply the sources I use for these particular cartridges. I only load for those three and 6XC these days.

 

[GermanS1]

Fitter, here are a couple of short articles that might be useful to you.

http://riflemansjournal.blogspot.com/2011/08/reloading-pressure-by-any-other-name.html

http://riflemansjournal.blogspot.com/2011/02/cartridges-long-range-reloading-safety.html (this one is part 5 of a multi-part series, but it stands alone well).