[5150]

I have a box of 71 gr. plated RN labeled for .32 cal. I load those for my .32 ACP, but the question is can I use them for .327? I'm only using Titegroup and the Hodgdon web site shows a 77 gr. bullet as the lightest one for their .327 load data. The Hodgdon site also shows the 77 gr. bullet at .314 dia. and mine are .312, if that makes any difference. My reloading manual also shows a 77 gr. bullet (lead), and the lightest plated one at 83 grains.
For all you reloading gurus out there, is there any way to properly/safely load a 71 gr. bullet for .327? I'm finding it impossible to locate plated .32 cal. in the 100 gr. weight, and I wanna stick with Titegroup. Thanx for any help.

Sent from my Commodore 64 running Windoze 95

 

[mrerick]

Yes - it makes a difference.

Vary anything from the documented experiments in the reloading manual, and you're performing your own experiment. Do you have an instrumented barrel to confirm that the load you're considering would operate in safe pressure limits?

Components (like ammunition) are in short supply right now. Your best approach is to wait until the correct components become available again.

 

[5150]

Yes - it makes a difference.

Vary anything from the documented experiments in the reloading manual, and you're performing your own experiment. Do you have an instrumented barrel to confirm that the load you're considering would operate in safe pressure limits?

Components (like ammunition) are in short supply right now. Your best approach is to wait until the correct components become available again.

Thanx for your reply. The .327 I have is a 3" Ruger SP101. I've put a boatload of various factory .32 caliber rounds thru it, so I'm accumulating a bunch of brass. And I don't know if it has an "instrumented" barrel or not. That sounds like some technical engineering term I'm not familiar with.

Sent from my Commodore 64 running Windoze 95

 

[mrerick]

When the component manufacturers do their load experiments, they have guns with barrels that have piezo electric measurement elements. These are essentially strain gauges that put out an electrical signal in response to the pressure measured in the gun's chamber as the cartridge fires.

Typically, these will measure one or more pressure peaks depending on the load and conditions. The pressure peaks occur at time of ignition, just prior to movement of the bullet out of the cartridge, just as the bullet reaches the leade into the barrel rifling, and as the bullet gliding surface engages with the rifling.

If these measured pressures are safely below the maximum pressures defined by SAAMI for the cartridge, the load is considered for publication. Various safe loads are also measured for consistency and accuracy. The best make it to the reloading manuals.

Reloading manuals are not "recipe books" that you can use as "guides" for making loads. They are precise documentation of measured experiments that performed safely within SAAMI specifications for the cartridge.

Modern firearms are designed to SAAMI specifications that ensure safety at the published pressure levels.

You don't have a "natural feel" for 35,000 to 80,000 PSI. Make little changes like a lighter undersized bullet, and what exactly does it do to the safety of the load? You can't tell without measuring it.