Erratic Velocities

[eng30312]

I just got my wife a S&W 632 in 327 federal magnum which I really like. The 115 grain golddots are getting 1345 fps over my chronograph. I look at it like a 9 mm which fits into a J frame (along with five more of its buddies ).

The problem I’m having though, is that I’m trying to make some loads in 32 H&R for light target loads and I am seeing about a 150 fps extreme spread in velocities.

I know that small cases are more sensitive to small variances, but I am a truly anal retentive reloader, especially with test lots. So far I’ve used AA#5 and AA#7 with 100gr Rainier FP plated bullets. Both loads were a few tenths below max. Before I spend any more time messing with this, does anyone have any experience with loading 32’s? What am I doing wrong here?

 

[altitude_19]

What kinda scale are you using?

 

[SHR970]

I don't have much experience with #5 but I have burned many pounds of #7 in several calibers. #7 DOES NOT perform well at low pressure this is a powder that likes to be run hard. Full house 32 H&R is only 21k psi. and you are probably running below 20k psi with your loads. Even though it isn't a caliber that you specified, 32 auto operates at lower pressure and you'll find that Accurate lists #2 and #5 powders for it. #5 velocities in this caliber are lower than #2.

If you want to run light loads, change to powders in the W231, Green Dot, Red Dot speed range. I have run all three of these powders in 32 S&W (both Short and Long) load development for my Single Six 32 H&R and they work well at these lower pressure levels.

#7 runs fine in this caliber with loads that exceed SAAMI max. for H&R mag. in my gun based on my load development.

 

[eng30312]

What kinda scale are you using?

I have a Redding #2 scale.

 

[eng30312]

I don't have any #2 right now, but I do have TiteGroup which worked the best of all the powders I tested a few years ago finding the best load for very light 38 Special target loads. I think I'll give that a whirl.

 

[ArchAngelCD]

While the conventional wisdom is you "must" have low SD numbers if you want good ammo may not always be true. I have sent a lot of factory ammo over the chrono the while I though the SD numbers were too high some of that ammo will produce very small groups. If the ammo you are making is very accurate don't worry too much about the SD numbers. Of course if the accuracy is off you will have to make changes...

 

[Walkalong]

It is not unusual with light loads in long cases to get a wide ES. Some powders are less position sensitive than others. Shoot six over the chrono with the powder against the primer, and then six with the powder against the bullet, and see how much difference you get. You might see a 200 to 300 ES this way. Another powder may do better.

One way to help get around this with light target loads in .32 Long/Mag/.327 Federal is to load a WC which takes up a lot of case space, leaving the powder to fill the empty space much better. A fast, low nitro, powder can help as well. I like AA #2, WST, or N310 with WCs in .32 Long and .32 Mag brass for a light plinker/informal target load.