Bolt Action pressure limits thoughts
#1
Was comparing load data for pressure limits for the following cartridges. When weighing in the age old 6mm ppc sane loads I am considering Hornady upper limits for Bolt guns may be a bit extreme. A additional reason for the consideration is primer pocket life on upper end bolt action loads.

On the other hand 6.5 grendel bolt action load data may be a bit overly conservative by some folks views.

6mm PPC max pressure 58,800 PSI
6.5 Grendel Gas gun 52,000
6.5 Grendel bolt gun font= 52,000
6mm ARC gas gun 52,000
6mm ARC bolt gun 62,000
22 ARC gas gun ?
22 ARC bolt gun ?
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#2
Primer pocket life most definitely is a consideration, but I don't think 62K is too high unless the brass is soft. I'm shooting a Savage, so no concern about the strength. When I see ejector plunger marks I know I'm beyond the limit whether it be this 6ARC bolt, or 556 or 300BO gas guns.
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#3
For me, simply staying within advertised pressure limits works fine. The more important considerations are typically barrel length, for more MV, the right powder, and an accuracy node for my barrel as shown on the target (typically also means consistent MV with small sd, usually <10). Sometimes, esp in a bolt action, you can use a longer OAL to get a bit more powder but even that might only get you to the next higher node.
Max MV, or max pressure, hasn't really gotten me that, so it may be academic but I don't really spend a lot of time thinking about it.
100 fps increase usually amounts to about 50 yds extra distance for a given velocity. Try it on the ballistic app of your choice.
my 2 cents.
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#4
Why do you suppose Hornady offers load data at a considerably higher pressure for bolt action rifles when no sources of load data offer higher pressure limits for 6.5 Grendel bolt gun applications? Is the 6mm ARC brass tougher than 6.5 Grendel brass?

I really do not think so. Someone enlighten me.
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#5
Pure specualtion, but the 6.5 Grendel was designed for the AR platform, so 52K limit due to bolt issues in gas guns. I have no doubt that 6.5Grendel Starline is equal to 6ARC Starline, so see no reason to not load a boltgun accordingly, but that's me.

Brass of a particular caliber will vary in volume and temper depending upon the manufacturer and lot. I've had factory brass split necks on the first firing with modest loads, and am aware of 350L factory ammo that stretches primer pockets due to soft brass.
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