Unexpected results 38 spl.

Chuck59 said:

a fair amount of powder landed on the bench, too. (?) This is what's left in the bag. Hmmm.
Could there have been some other powder in them? Could there have been a mix of powder and a pressure spike? Dunno. Note to self. Buy new brass from now on.

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Is it powder or tumbling media? I’ve gotten shiny brass at gun shows and there’s a bit of media in the bags. You can always clean a few and try your loads again.
I load a Bayou Bullet 138gr button nose wad cutter that’s coated. It’s not the same as yours, obviously, but with Titegroup at 3gr, 1.26 OAL, its moving 853fps out of a 6” 686. I need 3.4 gr to get it to 916fps.
Is this a new jug of Titegroup? If so, maybe it’s hotter than normal?

That random detris in the baggie, scoop some up and see if it burns like gunpowder or crushed walnuts. Should be pretty easy to guess which of the two it is.

I wouldn't think it'd be gunpowder, but if it is that could explain some things. Stranger things have happened I guess.

I've seen strange things happen with Titeboom I call it. Just my experience and opinion. To each his own.

fxvr5 said:

Read those posts again and again. Look very close for the 'same weight' and 'loaded to the same overall length' clue.

edited to add 'same weight'

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The "clue" is proving your theory wrong. Same weight and same seating depth have nothing to do with the volume of a hollow base bullet cavity added to the volume of a case, no matter how deep or shallow it's seated. Know anything about internal combustion engines? If you had a piston that only had valve cut outs and one that had a deep dished top, which would produce a higher compression pressure? Same weight, same travel, but smaller volume...

This is a silly argument, I'm done...

Walkalong said:

A reasonable assumption, but something is wrong. My thing is it sounds like you have the recoil to go with the velocity the chrono gave. Maybe not, hard to tell.

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I tend to agree. No way should you be getting that much velocity and with your experience with shooting the gun, you know when recoil is excessive. Powder still in the brass? Could be brass from pulled loads and no telling what kind of powder. Could it make that much of a difference? Kinda depends on the powder, but blending it with another, would change the characteristics of both.

mdi said:

The "clue" is proving your theory wrong. Same weight and same seating depth have nothing to do with the volume of a hollow base bullet cavity added to the volume of a case, no matter how deep or shallow it's seated. Know anything about internal combustion engines? If you had a piston that only had valve cut outs and one that had a deep dished top, which would produce a higher compression pressure? Same weight, same travel, but smaller volume...

This is a silly argument, I'm done...

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Holy cow. Maybe pictures will help.

mdi said:

The "clue" is proving your theory wrong. Same weight and same seating depth have nothing to do with the volume of a hollow base bullet cavity added to the volume of a case, no matter how deep or shallow it's seated. Know anything about internal combustion engines? If you had a piston that only had valve cut outs and one that had a deep dished top, which would produce a higher compression pressure? Same weight, same travel, but smaller volume...

This is a silly argument, I'm done...

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One last try. Real Berry's bullets. Plain base 148 grain wadcutter, and hollow base 148 grain wadcutter. Same weight.



The two bullets on the left are Berry's 148 grain 38 caliber double end wadcutters. (The top and bottom of Berry's double end wadcutter bullets look the same.) The two bullets on the right are Berry's 148 grain 38 caliber hollow base wadcutters. Note the hollow base wadcutter on the right is LONGER than the bullet on the left, even though they are the same weight and caliber (.357).

The 148 grain wadcutter is .555" long. The 148 grain hollow base wadcutter is .610" long.

How can bullets of the same weight be different lengths? Because lead has been 'removed' from the bottom center of the hollow base bullet (to form the hollow base) and 'added' to the skirt of the bullet's side (hence the term displaced).

They are seated to the same overall length (see post 18), NOT the same seating depth. Same overall length means the same overall length of the loaded cartridge, also called cartridge overall length.

Since they are seated to the same overall length, the hollow base wadcutter will appear to be seated deeper - if you're going by looking at the base of the bullet because the hollow base bullet is longer. This would suggest that the hollow base bullet takes up more space in the case, not less space. But it doesn't. The two bullet designs take up EQUAL SPACE in the case.

The difference in bullet length of the two bullets is because the lead was DISPLACED - moved from the central base to the bullet's sides (skirt of hollow base) of the hollow base bullet. The volume of lead is the same for both bullet shapes (it's just shaped differently), so they occupy the same volume of space in the case.

I have a S&W 637 Airweight rated for +P loads. Recently I tried Trail Boss powder because I wanted better case fill. I'm shooting Speer 158 grain cast Truncated Cone wadcutters. A 1cc Lee Dipper Cup is ~4.1 grains of powder and near max for standard 38 Special loads. It's pretty snappy.but still very controllable in the snubby.

I know this has nothing to do with your original question but Trail Boss is something you might consider.

flashhole said:

I have a S&W 637 Airweight rated for +P loads. Recently I tried Trail Boss powder because I wanted better case fill. I'm shooting Speer 158 grain cast Truncated Cone wadcutters. A 1cc Lee Dipper Cup is ~4.1 grains of powder and near max for standard 38 Special loads. It's pretty snappy.but still very controllable in the snubby.

I know this has nothing to do with your original question but Trail Boss is something you might consider.

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I really like Trailboss in my 38 Special ammo I use for IDPA. Shoots soft and clean.