Unexpected results 38 spl.

[Chuck59]

Hi folks. Last summer I bought 500 Acme 148 gr. BNWC-NLG wad cutters. Thought I'd load some for my little S&W snubbie. It's my first high tech coated bullet.
Lyman data says start 3.1 gr Titegroup at 1.317" oal for a different 148 gr. wad cutter.
This bullet has a cannelure, though, and seating it there results in an oal of 1.290.
So.
I loaded 5 at 2.8 gr. Titegroup at 1.290. Seemed reasonable to me.
My crono said 1044 fps, and recoil was (ahem) a little heavy. Thought, "***??" Did I over charge one?? Pulled the other 4, and they were right on 2.8 gr. Hmmmm. Tried one more..1053. +P and some..
This is the first time that I really don't understand what is going on with a load. What's up?

 

[PapaG]

Was the data for a hollow base wadcutter" That would raise pressure on your solids.

 

[Chuck59]

Was the data for a hollow base wadcutter" That would raise pressure on your solids.

It's for the Lyman 358091, which as far as I know isn't a hollow base.
Says 3.1 gr TG @ 1.317 to start, 854 fps.
Thanks for the reply..

 

[Jim Watson]

You are in Hodgdon's range, although they did use a hollow base wadcutter.
I can't explain the phenomenon but would calibrate and check weigh the scale. And use less powder.

 

[fxvr5]

Was the data for a hollow base wadcutter" That would raise pressure on your solids.

Why's that?

 

[Gumby0961]

What even makes more disturbing is that was out of a snubby.

 

[whughett]

1) Use a check weight on your scale to set to zero and verify it’s accuracy.
2) Do you trust your chronograph.
3) Those velocities seem high, especially out of a 2inch Barrel. Most wad cutters are traveling closer to 800 FPS. What was the published velocity ?
4) Recoil, perceived or actual can feel high in such a light weigh short barrel revolver. Heave you tried factory Ammo.
5) I have zero experience with coated bullets, these are coated ?, perhaps that could affect pressure, was the data for lead or jacket.
6) In this case OAL shouldn’t make a difference. Wad cutters normally set flush with case mouth. What does the BN signify?
7) Are there any excessive pressure signs. Flattened primer, hard to extract, etc

 

[WestKentucky]

That had to have some thump to it. Even for HiTec that is a bit fast. The shortened OAL would account for a bit of a pressure increase but not anything that would cause THAT. I would back off to about 2.6 and see how things go. Shortening the case does change things, you might want to look at top end charges for 38SW and use comparable weights and profiles to estimate things. I would not normally suggest such foolishness as using data for another cartridge, but if you look at the case dimensions you will probably understand why I do this when I load 38s short. A lot of competition shooters short load 38s or even cut cases short to shave time off of reloads, so you might want to investigate some of those loads too. Be careful and report back.

 

[Chuck59]

You are in Hodgdon's range, although they did use a hollow base wadcutter.
I can't explain the phenomenon but would calibrate and check weigh the scale. And use less powder.

1) Use a check weight on your scale to set to zero and verify it’s accuracy.
2) Do you trust your chronograph.
3) Those velocities seem high, especially out of a 2inch Barrel. Most wad cutters are traveling closer to 800 FPS. What was the published velocity ?
4) Recoil, perceived or actual can feel high in such a light weigh short barrel revolver. Heave you tried factory Ammo.
5) I have zero experience with coated bullets, these are coated ?, perhaps that could affect pressure, was the data for lead or jacket.
6) In this case OAL shouldn’t make a difference. Wad cutters normally set flush with case mouth. What does the BN signify?
7) Are there any excessive pressure signs. Flattened primer, hard to extract, etc

Checking the scale was the *first* thing I did. Yeah, right on the money with my beam scale and digital.
I've shot this little booger a fair amount.. recoil was considerably higher than normal.
Data is for lead. Yes, these are high tech coated.
Not hard to extract, but I'm certainly not going to beat up this gun with this load. I'm just trying to understand what is going on.. oh, forgot.. light crimp, too.

 

[whughett]

Checking the scale was the *first* thing I did. Yeah, right on the money with my beam scale and digital.
I've shot this little booger a fair amount.. recoil was considerably higher than normal.
Data is for lead. Yes, these are high tech coated.
Not hard to extract, but I'm certainly not going to beat up this gun with this load. I'm just trying to understand what is going on.. oh, forgot.. light crimp, too.

So I’m assuming you checked data for, if it’s there, a jacket bullet of comparable weight. I’d also cross check several times

Would you know if that little booger is rated for plus p loads.

Titegroup on line data list the start as 2.7 and 3.3 as max for that bullet weight. You may well be pushing the envelope.

 

[joneb]

Is this the bullet? http://www.acmebullet.com/bullets-reloading-brass/38-CAL-Lead-Cast-Bullets/38-148-BNWC-NLG if so it's a 92-6-2 alloy with a bhn of 16, plus there are no lube grooves which means a increase of bearing surface. Add to that they are sized to .358" I would use a slower powder with this bullet accurate #5 or VV n340 come to mind.

 

[ArchAngelCD]

Change your powder with that bullet to something like W231/HP-38. The Acme bullet doesn't look like the normal WC bullets I have loaded.

 

[PapaG]

Why's that?

More room in the case with a h.b.w.c. by the volume of the hollow base.

 

[Chuck59]

Is this the bullet? http://www.acmebullet.com/bullets-reloading-brass/38-CAL-Lead-Cast-Bullets/38-148-BNWC-NLG if so it's a 92-6-2 alloy with a bhn of 16, plus there are no lube grooves which means a increase of bearing surface. Add to that they are sized to .358" I would use a slower powder with this bullet accurate #5 or VV n340 come to mind.

Thanks for that..makes perfect sense.
I tried N330 because that's what I have for 9MM. Also Bullseye.
Both acted as I would expect.

Change your powder with that bullet to something like W231/HP-38. The Acme bullet doesn't look like the normal WC bullets I have loaded.

Yeah, it's a button head.. supposed to fly better from the (little) research I've done. I do have *some* HP-38, but didn't try it. How about Unique for a slower powder?
Thanks for the replies, gentlemen. I'll just save the TG for another load.

 

[RealGun]

Have you shot a bullet that heavy before (in that gun)? You could get a good wallop in a lightweight snubbie that normally shoots 110 grain.

Is 148 the actual weight of the bullets?

 

[Chuck59]

Lots of em.. but not *this* bullet.

 

[joneb]

Yeah, it's a button head

I like the discontinued Speer 148gr button nose swaged WC with the flat base. One of my favorite 38 spl loads for a S&W 36 w/a 1 7/8" barrel is 3.5gr of Bullseye and a GM 100 primer. I use a light crimp at the crimp groove the COL is 1.3" the brass is trimmed at 1.145"
https://www.thehighroad.org/index.php?attachments/reloading-jpg.76236/ this is how they shoot from a S&W mod 10 w/a 6" barrel. On the target it I wrote 148gr swc my bad should have been 148gr wc.

 

[fxvr5]

More room in the case with a h.b.w.c. by the volume of the hollow base.

If a hollow base wadcutter and a plain (non-hollow) base wadcutter bullet of the same weight are seated to the same overall length, there is no difference in remaining case volume. The hollow base does not create more space in the case.

 

[sequins]

If a hollow base wadcutter and a plain (non-hollow) base wadcutter bullet of the same weight are seated to the same overall length, there is no difference in remaining case volume. The hollow base does not create more space in the case.

Not so.

The hollow portion of the base, the skirt, is seated inside of the case but the empty volume within the skirt remains empty.

A solid base it's not empty, so less volume. Should be a slight difference.

 

[fxvr5]

Not so.

The hollow portion of the base, the skirt, is seated inside of the case but the empty volume within the skirt remains empty.

A solid base it's not empty, so less volume. Should be a slight difference.

Nope. No difference in remaining case volume when two wadcutter bullets (but different base design) of the same weight are seated to the same OAL.

 

[Slamfire]

What where the velocities for 5 at 2.8 gr. Titegroup at 1.290.?

Did you shoot a "calibration" round over the chronograph? I do, my calibration round is a 158 LRN with 3.5 grains Bullseye in a 38 Special case. I have fired enough of these rounds to know if the chronograph is out of alignment. I have been shooting down a case of 22lr Rem Target SV for rifles. The velocities you measured are unreasonable for a 148 grain bullet with 3.1 grains Titegroup, especially for a snubbie!

Either you put a lot more powder in the case or the chronograph was off axis, or powder residue confused the machine. What type of chronograph did you use?

 

[Walkalong]

@fxvr5 is correct. The alloy may be a bit different, but it won't make a big enough difference to worry with. Same weight, same basic volume, so same basic free space in the case if seated to the same OAL.

 

[Walkalong]

OP, you loaded a shorter OAL with a different style bullet and did not start at the minimum. While I cannot say I have never done this, and guessed wrong as you did, that is what got you in trouble. Been there, done that. Welcome to the club, it tends to make us more careful after that.

Y'all be careful out there.

 

[Walkalong]

to know if the chronograph is out of alignment.

This can surely make a difference in the velocities read, I am real careful to line up the chrono as close to true as I can each time.

 

[whughett]

I have an H&G mould that throws a 148 Grain wad cutter with a small dome. Never knew it was called a button nose. It’s a nice bullet and makProblem is I can’t load it for the 38 WC’s I shoot in the Mode 52 S&W, unless I load it up side down.

Nice thread I’ve learned a few things.