[mongoose33]

Been shooting a ton of cast bullets (mine I get from Missouri Bullet), but bought a load of FMJ 230gr from Precision Delta.

I've been working up loads with both 231 and WST, went to the range to Chrono them today.

My max load on 231 was 5.7 grains, but that only produced 756 fps average.

My max load on WST was 4.7 grains, and that only produced 725 fps average.

These out of my XD-45 Service with the 4" barrel. OAL is 1.250.


Does anyone have any pet loads for this combination? WST is particularly hard to find (despite FredJ's efforts .

It seems to me I should be able to duplicate the original .45 load at 850fps or so, and these aren't even close.



The confusion stems from this: I've run Hornady's XTP 230 HP through this same gun, with 5.7 grains of W231, and generated velocities in the mid 850s.

Of course, the bullets are probably to blame, but they were also very accurate, so that doesn't seem the likely culprit unless the bearing surfaces are radically different.

 

[fredj338]

OAL matters, I doubt you were running the XTP that long, probably closer to 1.220"OAL? You are going to lose about 25fps in the shorter 4" tube. My loads for the 230grRNFMJ (Win):
5.7gr W231 @ 1.255" = 840fps from (2) diff 5" guns.
4.7gr WST will get me just above 800fps, same guns.
Factory 230gr ball ammo is likely to run right around 800fps in most 4" guns, so that would be the velocity & would be looking to reach.

 

[mongoose33]

OAL matters, I doubt you were running the XTP that long, probably closer to 1.220"OAL?

The XTPs are at 1.23".

You are going to lose about 25fps in the shorter 4" tube. My loads for the 230grRNFMJ (Win):
5.7gr W231 @ 1.255" = 840fps from (2) diff 5" guns.
4.7gr WST will get me just above 800fps, same guns.
Factory 230gr ball ammo is likely to run right around 800fps in most 4" guns, so that would be the velocity & would be looking to reach.

I ran some Winchester WB 230 gr ball through yesterday as well, just as a comparison; averaged 785fps. Same gun, same day.

The earlier XTP data was out of the same gun.

I checked the bearing surfaces on both bullets; they appear to be almost exactly the same.

Around 800fps is what I'm actually looking for, Fred; I'm just surprised that I can't achieve that. I'm bumping up against what most reloading manuals apparently consider max for the 231, and of course, there's no such data for WST.

The most surprising thing for me is that the XTP and 231 produces 100fps greater out of the same gun.

 

[fredj338]

The XTPs are at 1.23".



I ran some Winchester WB 230 gr ball through yesterday as well, just as a comparison; averaged 785fps. Same gun, same day.

The earlier XTP data was out of the same gun.

I checked the bearing surfaces on both bullets; they appear to be almost exactly the same.

Around 800fps is what I'm actually looking for, Fred; I'm just surprised that I can't achieve that. I'm bumping up against what most reloading manuals apparently consider max for the 231, and of course, there's no such data for WST.

The most surprising thing for me is that the XTP and 231 produces 100fps greater out of the same gun.

IME, the XTP has a much longer bearing surface than any RNFMJ & they seat deeper, so I would expect higher vel. You have some room to run, Speer goes to 6.2gr of W231 under a RNTMJ. Hodgdon is running to 4.9gr & seating the 230grTCFPFMJ to 1.200" OAL. I have easily run to 4.8gr under a 230grRNFMJ, but consider that the top end. I would move to W231 for more vel than the 820fps or so I cna squeeze into std pressure w/ WST.

 

[mongoose33]

IME, the XTP has a much longer bearing surface than any RNFMJ & they seat deeper, so I would expect higher vel. You have some room to run, Speer goes to 6.2gr of W231 under a RNTMJ. Hodgdon is running to 4.9gr & seating the 230grTCFPFMJ to 1.200" OAL. I have easily run to 4.8gr under a 230grRNFMJ, but consider that the top end. I would move to W231 for more vel than the 820fps or so I cna squeeze into std pressure w/ WST.

I checked the bearing surfaces; the HTP does have a longer bearing surface than the FMJ ball.

I'm always a little unclear why a longer bearing surface will result in higher velocity.

I'd think that the greater friction would result in lower velocity. I'd also think the slower (slowed by friction) bullet would allow pressure to build to a higher peak, which would result in higher velocity.

So, Fred, what's really going on?

 

[fredj338]

I checked the bearing surfaces; the HTP does have a longer bearing surface than the FMJ ball.

I'm always a little unclear why a longer bearing surface will result in higher velocity.

I'd think that the greater friction would result in lower velocity. I'd also think the slower (slowed by friction) bullet would allow pressure to build to a higher peak, which would result in higher velocity.

So, Fred, what's really going on?

My bet is higher pressure by increased friction. All things being equal, higher pressures usually result in higher vel. You see this when loading moly coated bullets. The identical bullet but moly coated, has less pressure & less vel, so you can & need to use more powder to get higher vel. Same thought in a bullet w/ longer bearing surface. The original Barnes 'X' in rifles was notorious for higher pressures vs a bullet of identical weight but shorter bearing surface. Then they put grooves in it to reduce bearing surface allowing for lower pressures & still getting high vel.
I also believe this is the case w/ lead bullets. Some say lead bullets offer less friction than jacketed, based on the idea that you can push a lead bullet thru a bbl easier by hand. Not so much IMO. A lead bullet is softer & more malleable, allowing it to move down the bbl more easily but then the lead also obturates to seal the bore better allowing a higher pressure to be obtained, higher vel w/ less powder. If the bullet had less friction, it would need higher pressure/more powder, to achieve the same vel. That is my theory based on shooting very sim shaped lead bullets vs jacketed & load data from moly coated bullets ALWAYS needing more powder to overcome less friction & achieve higher vel.

 

[mongoose33]

Thanks, Fred. Still trying to figure out the physics and dynamics of all this. Sounds like I can go up a little on both loads, see what happens to velocity.

 

[fredj338]

Thanks, Fred. Still trying to figure out the physics and dynamics of all this. Sounds like I can go up a little on both loads, see what happens to velocity.

Yep, depends on your gun, but there should still be some room to run. Me, I am quite happy feeding my 45s nothing but lead bullets, but I do load jacketed & plated @ times for certain guns or indoor shooting. Then again, I hate shooting indoors.

 

[mongoose33]

I loaded up a few more rounds today, I bumped the WST to 4.9, and the 231 to 5.9.

I still have all my fingers.

WST: 4.7 gr, 725 avg...4.9 gr, 766 avg. (six rounds)

231: 5.7 gr, 756 avg......5.9 gr, 789 avg (five rounds)


The 231 load was the most consistent I've ever shot--ES of 9, and a Standard Deviation of 3. Only five rounds, but still.....

The 231 load approximates what the WWB ammo did.

I think that's about as high as I want to go. I might diddle with OAL a bit, see what happens if I shrink it a bit.

 

[fredj338]

I loaded up a few more rounds today, I bumped the WST to 4.9, and the 231 to 5.9.

I still have all my fingers.

WST: 4.7 gr, 725 avg...4.9 gr, 766 avg. (six rounds)

231: 5.7 gr, 756 avg......5.9 gr, 789 avg (five rounds)


The 231 load was the most consistent I've ever shot--ES of 9, and a Standard Deviation of 3. Only five rounds, but still.....

The 231 load approximates what the WWB ammo did.

I think that's about as high as I want to go. I might diddle with OAL a bit, see what happens if I shrink it a bit.

You could just have a slightly slow bbl; oversize chamber, oversize groove dia or both, &/or slightly undersized bullets. Did you mic them? It doesn't take much to reduce pressures & vel falls off. Lyman say 5.8gr of W231 is max, Speer says 6.2gr both w/ the TMJ. Still, going much over 6gr is pushing hard IMO.