How much less powder when switching from 115gr to 124gr

[evilbeef54]

I am currently running 9.1gr of silhouette with a Montana Gold JHP 115 gr with win SRP loaded to 1.235 in 38 super comp to give me 171 PF in my open gun.

A friend is giving me some 124gr MG JHP to test out, how much less powder should i be running to account for the bullet weight?

yes i will be using a chrono for load devolopment, just looking to see what a good starting point should be, and how much a differnce in powder it should be

Thanks

[Hi-Power Jack]

I'd start at 8.0 and work up slowly.

The OAL will also be important - and you might want to run

The Plunk Test again with the new bullets.

[evilbeef54]

Ok, thanks!

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[Bamboo]

As a data point:

38 Super - 5.4" Schuemann with 3 holes

MG 124gr JHP @ 1.235"

Sillhoutte @ 8.3gr

Wolf SPM primer

= 172 power factor

I'd probably start around 7.2 - 7.5 grains just to be safe.

[USNRET]

Here's an idea. Look at what your reloading manual says.

[evilbeef54]

Honestly didn't even think to check the manual since loading to major PF is usually outside what it lists, but thanks for the super helpful response! You must have been a boatswain's mate, LOL

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Edited May 15, 2016 by evilbeef54

[USNRET]

Honestly didn't even think to check the manual since loading to major PF is usually outside what it lists, but thanks for the super helpful response! You must have been a boatswain's mate, LOL

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Nope. I was Aircrew. The type that got per diem.

[evilbeef54]

Ahhhh.... That explains the fascination with manuals, haha jk

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