357 Sig minor PF loads

[SuperDuke]

Before anyone asks "Why bother with 357 Sig minor loads?" I use it for comps other than IPSC.

Is anyone else out there shooting minor power factor loads in 357 Sig? I've been loading 4.5gr AP70 and 135gr RN but am getting up to 100fps variation through the chrony (between 900 and 1000fps). I'm not sure if it is just a cheap chronograph (borrowed a mates and can't remember the brand) or if the powder thrower on my 550 is throwing an occasional light charge. When reloading i check the powder every 50 rounds and it's always on the mark and use the Lee FCD, I shoot it out of an Edge with a 13lb recoil spring and it always cycles fine.

I don't get anywhere near the velocity spread with the major loads (6.4gr AP100 and 160gr RN).

Any thoughts / advice / suggestions would be appreciated.

[dansedgli]

That's a bit under the minimum charge in the manual.

I'd start at the min charge and see how that goes.

Could be very similar to a revolver load PF issues.

If you load a round & point it to the ground, allowing all the powder to move & settle at the front of the case, the PF will be very low.

If you load a round & point the gun upwards, allowing all the powder to move & settle at the rear of the case, the PF will be very high.

This is one of the reasons why it's advisable to use a dense powder, that takes up most of the available room in a case.

Try it, you will be amazed.

[SuperDuke]

Dansedgli,

I would use that load but it has a PF of 147 (according to the ADI data) which is way more than what I wanted. With the current load it shoots tight groups no worries and cycles fine. Wanted to know if anyone else is shooting minor and has had similar issues. It could be the chrono, the powder thrower or just the fact it doesn't like minor loads.

Cheers

[Vman9mm]

Try AP50 for minor PF loads in 357sig, more consistent burning with lighter loads than AP70 IMO

[ctguru]

Bit of a thread hijack

What major PF loads are people using, I assume AP100 and about 6.5--7.0grns, standard primer?

Also what 357sig dies are people happy with? Just bought a G35 and want to run major with a LWD barrel

Looking at getting some Dillon carbide, as the Lee aren't carbide.

[.357sig]

Before anyone asks "Why bother with 357 Sig minor loads?" I use it for comps other than IPSC.

Is anyone else out there shooting minor power factor loads in 357 Sig? I've been loading 4.5gr AP70 and 135gr RN but am getting up to 100fps variation through the chrony (between 900 and 1000fps). I'm not sure if it is just a cheap chronograph (borrowed a mates and can't remember the brand) or if the powder thrower on my 550 is throwing an occasional light charge. When reloading i check the powder every 50 rounds and it's always on the mark and use the Lee FCD, I shoot it out of an Edge with a 13lb recoil spring and it always cycles fine.

I don't get anywhere near the velocity spread with the major loads (6.4gr AP100 and 160gr RN).

Any thoughts / advice / suggestions would be appreciated.

I used to download for shooting service match etc
I will have to go back over my data to see what the actual loads were, but I was using AP70 with 165gn topscores, and I wasn't getting huge variation in MV.
(in an STI edge).