6 super lr primers and velocity

[Julien]

Gooday all ,I was at the range yesterday working up a load using h 1000 and berger 105 hunter vld bullets.
Previously I was using berger 105 vld target bullets, with 46.5gr of h1000 cci lr primers and 105 vld target bullets I was getting about 3125fps avg speeds.
When I switched to the 105 hunter bullet with the same load I was down @ about 2975 fps [I figured the thiner jacket caused less pressure],so I bumped the load up to 47.5 gr h 1000 and was @ 3025 avg.

So I am thinking maybe it is because it is a bit cooler now than it was earlier in the season ,I decided to try some magnum primers to compare and the speeds immediatly went back up to 3160 avg.

Should I be using magnum primers from now on?

The groups were not as good as what is used to group when it was warmer, maybe I should try another powder.

 

[oneflyer]

Caliber?????

 

[Jeffvn]

with LR primers, the magnums usually have a hotter flame. I know that sometimes, in colder conditions, Reg primers do not adequately ignite a powder column. My experience with this relates to a 7SAUM, Berger 180 vlds, H4831SC, using Fed 210M regular primers in cold conditions (29 degrees) versus Federal 215M in the same conditions. For the 6 Super LR, I'm not so sure the smaller overall volume would have similar effects, but I would not be overly surprised if it did.

I agree that one of the reasons folks try to stick with regular primers is the consistency of burn/flame; they just seem to be more consistent with regular primers.

Sorry its not much of an answer, but it certainly seems to be what happens when I shoot in with the temperature in the 20s and 30s.

JeffVN

 

[fullersson]

If you decide to try a different powder I would try N160. I ran 46.0gr of H1000 in my .243win and 43.5 of N160 with good accuracy results out to 550 yards. I think with the 6SLR that H1000 would probably be the better powder if you could get the pressure up but N160 is worth a try and I would stick with the BR-2 primers. With N160 you won't have any trouble getting the pressure up so work that load up slow. Brian Brown.