7mm sherman max

Mine seems to like 63.6 gr for grouping with formed brass. That puts it right at 2,980fps and 0.3 MOA. I've only been able to find N570 now so back to the drawing board for new load data for a while. The barrel is Bartlein #3, 26" 1:8.5
I have a good load for the 175 EH with 62 RL23. It shoots one hole at 3011'
 
Its on a lot of store shelves

It'll be on MY shelf tomorrow then. I've only found oddball stuff here in Houston in the past few months. I run 7828 in my 300 wby and 300 wsm and both drive tacks - I assume that's not a powder the Max would play well with? Everything else I stocked up on powder for is either 4350 (H & IMR both) and cfe223. Next time (heaven forbid) I'll be better prepared.
 
It'll be on MY shelf tomorrow then. I've only found oddball stuff here in Houston in the past few months. I run 7828 in my 300 wby and 300 wsm and both drive tacks - I assume that's not a powder the Max would play well with? Everything else I stocked up on powder for is either 4350 (H & IMR both) and cfe223. Next time (heaven forbid) I'll be better prepared.
7828 would likely work
 
Finally got my 7 Max put together, so I figured I'd share some data. Barrel is a 20" CarbonSix, 8 twist.

****Standard disclaimer: These are max loads in my rifle. Start low and work up****

180 ELD-Ms, RL 26, .02 off the lands (COAL 3.034):
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195 Berger EOLs, RL 26, .02 off the lands (COAL 3.112):
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Bolt lift started getting ever-so-slightly heavier at the top 2 charge weights, and the brass showed signs of pressure. Lowest charge weight is top left, then progresses as you go down, with top right case being the highest charge:
Brass.jpg


I plan on exploring the velocity flat spot on the 195s centered around 61.5 grains next and going from there. So far I'm pleased with it!
 

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Good work.
Those data correlate pretty well with my testing from a 26" barrel. Looks like about 25'/inch of barrel.
It would be interesting to see what about 3 grains less of RL23 would do with that length barrel
 
Another powder to investigate is VV N165. I have been fireforming 7SS cases with it and it worked as well as H1000. Since I have several championship matches coming up and my supply of H1000 may not hold out and not likely to get more I have done a workup with N165 in my match loads also and it shoots as well as H1000 and gives a little better velocity for the same weight of charge. I know it is a different case but it may be a viable option in the Max.
 
Good work.
Those data correlate pretty well with my testing from a 26" barrel. Looks like about 25'/inch of barrel.
It would be interesting to see what about 3 grains less of RL23 would do with that length barrel

Interesting. I don't know much about RL23. Think it has the potential to do similar velocities to RL26 with this short barrel then?

Good information and nice layout. I hope you try 180 Berger Hybrid and the 175 Berger in your testing.

Thanks. I don't have any plans to test the 175s or 180s at the moment, but you never know.
 
Interesting. I don't know much about RL23. Think it has the potential to do similar velocities to RL26 with this short barrel then?



Thanks. I don't have any plans to test the 175s or 180s at the moment, but you never know.
I dont know if it will keep up or not, but I think its worth a try
 
Seems like it's worth testing out then if I can find it in stores. Sounds like it's not as erratic in high temps as RL26, so that would be nice.
 
Anyone have a pet N570 load with Berger 180's? I'm toying with 8727 also but so far only have very accurate RL26 load data for my 26" 8,5 twist 7Max and I've been unable to source RL26 in the last couple months.
 
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