Using Rimrock RNFP bullets I loaded up 20 each using 1.8, 1.9 and 2.0 of Bullseye powder. Pistols are a CZ70 and a Zastava M70. At 25' my reloads are hitting 1 1/2" to 2 1/2" low with the 2.0 gn charge being the lowest. Groups are 2-3 times the size of groups with factory ball ammo, which shoots to point of aim at 25'. All loads cycled both guns so I may try a batch of 1.7gn BE before I try W231. Seating is a little shorter OAL than factory ball because the shape of the FP bullet. I'm using a FCT die in the last stage. The ball ammo was a mixed lot so no gaming there but I was getting honest 1.5" groups with it from the CZ70 with POI at POA. Any thoughts?

Just puzzlement. I load for several .32 ACP pistols and get decent, steady groups. It is a mild PITA loading a cartridge that physically small but seeing as factory ammo is both hard to find and hella expensive right now I just muddle thru. My normal bullet is a Berry's RN plated. Except for the fact I would expect your pistols to like plated or FMJ much better than lead I am at a loss.

I'm not opposed to trying Berrys RN if I have to but I'd like to get these Rimrock to work. I'm also not stranger to loading 32's, I started loading 32 S&W long in the mid 70's. Just never loaded 32 ACP before.

I'm not familiar with Rimrock; are these cast bullets? If so and they are shooting poorly, they may be of the wrong diameter for your gun or maybe the wrong alloy mix for your load or both. Best bet would be to try some other cast bullets, if possible. In a handgun cartridge, a cast bullet of the right alloy and proper fit should at least equal the accuracy of a good jacketed bullet, but the best cast bullet isn't often easy to find if you have to rely on commercial cast bullets.

Also, what is an FCT die? Is this like a Lee factory crimp die? You may not need it. Try your loads without it, and consider using a standard taper crimp die in place of it. Crimp only enough to keep the bullet in place under recoil, and no more. Good luck-

I have a batch of 32ACP I loaded in the 1990's. My loading manual says I used 84gr. or 90 gr. RN cast Lyman with 1.4 WW231. Those were for a "Belly Gun" Davis Derringer. I think this is the S&W short load, but it cycled my PPk

Ivan

I think your bullets are too heavy. These guns are set up
for 71 grain ball. The Rim Rocks are in the 100 grain range.
You need to go to cast boolits and read up on heavy 32 loads.

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These bullets are a 75 gn FP sized .313. I would not think the diameter would be an issue as I regularly shoot .358 cast bullets thru my 9x19s and they swag down nicely. By FCT I meant FTC, Factory Taper Crimp.

I'd still try some different bullets if you can find any these days. The Lee Factory Taper Crimp die if used right may do no harm, but it might be worth the effort and expense to go with a standard taper crimp die and compare results with the Lee die.

Would consider following rockquarry's suggestions. What happens in your 9mm may be irrelevant. All lead bullets are not the same hardness, and smaller caliber semi auto's from differing eras/places may not have the same bore dimensions. Some rifling grabs hold of jacketed bullets better, even if they are undersized. If your recording velocities, there may be some more relevant info. What seems really unusual is the hitting low part, which may be a good indicator of a higher velocity than normal, which would seem even more unusual given the loads you tried.

I have very limited chrono data for my 32ACP reloads, but from what little testing that I've done, I came away with the belief that for the 32ACP:

"Mo hotta, mo betta."

With 2.2 gr W231 under a plated 71 gr RN, I got only around 480 FPS with miserable SD (~20%) from a CZ50 (3-1/4" BBL). With 2.5 gr W231 and 60 gr XTP bullets, they went to 750 FPS with good SD (~4%) from a 2-1/4" Seecamp, which was comparable to factory Hyd-shock ammo from the same gun. I cannot tell you which was more accurate; my 32ACP handguns are more mouse and belly guns than target guns. -S2

I was in wrong and apologise. rockquarry has the best advice. Sorry.

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OK, I have some Barrys on order to try. In the mean time I'll try a different crimp die, which I have and maybe W231, which I have. I started to get a slight case bulge with 2.0 gns of BE, which surprised me. Maybe I have too much crimp raising pressure.

You're on the right track. Try as many different component combinations as possible. Many handloaders crimp far more than necessary.

Fire the pistol and then eject the next round unfired and take a close look at the bullet nose. They may be getting damaged in the feeding process.

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I pull a bullet or two and check the diameter. They may be starting .313 but unless the expander die is made for large diameter bullets they could be getting swaged down when being seated.

Reloading for European pistols can be a challenge. Chamber dimensions and bore diameters can be all over the place. Here’s a post that might help.

And here’s another thread on reloading heavy bullets in the .32 ACP.

Lastly, one more thread on reloading heavy bullets in .32 ACP.

And, here’s a video that has info on reloading for the M70 pistol. In the video the guy says his M70’s bore diameter is .309. Slug your bore and see what the diameter really is. That might be your problem.

My Walther PP has a bore diameter of .310 and I use an 80 grain .311 cast bullet. Anything bigger does not group well.

As far as the bore diameter goes in those Europen pistols, they are all over the place. My HSC is .309, where as the nominal diameter for the 32 acp is 311-312. I use the Lyman 311252 bullet, which weighs out at 77 grains. That bullet works best for me. My HSC shoots right to the point of aim, with that bullet. Drive a slug through your barrel from the breach to the muzzle. Put some oil or grease on your bullet, when driving it through. You can use a brass rod or a steel one that has some vinyl tape around it, to keep from scoring the rifling. Measure the diameter, and then you know. The fixed sights are usually regulated for the 71 to 80 grain bullets. Anything heavier, and you are in uncharted territory. Heavy bullets can be made to shoot well, but it takes some experimentation, and is it really worth the effort. That's my 2 cents worth.

@walnutred,
Lymans Cast Handbook 4th edition lists 2.5gr W231 as potentially most accurate with a 75gr FN Cast bullet. (that's the max load in the manual) Maybe your gun just doesn't like the Bullseye load.

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SWCA #3437

Does that manual list OAL? I tried plunk testing my loads and they failed the plunk test. So I sized a unprimed case and seated a bullet. After forcing the bullet in as far at a factory round went in I pulled it out and measured. OAL was only .926. Doing more research I found Buffalo Bore uses these same bullets in their 32 ACP +p, seated at .925. So my plan is to A: try a batch with 1.6 and 1.8 of BE at .925. Try some W231, at reduced loads and work up. If the bullet needs seated that deep it's going to reduce headspace above the powder noticeably.

Plan B is wait until my Berrys Bullets arrive and save the Rimrock for 32 S&W loads.

Ok, I just measured some Fiocchi 32 acp ammo. .975 oal. My reloads are .984, using the 311252 cast bullet. The Lyman manual shows .984 as the max oal. This figure is mainly based on what the magazine will handle lengthwise.

All my 32 acp handloaded rounds have a slight case bulge at where the base of the bullet is. I attribute it to the sizing die reducing the case diameter more than it has to, and I use .309 bullets.

I know your OAL are closer to the factory specs. One of the complaines about the BB 32 ammo is the potential for rim lock, but I suspect they have to be this short due to the RNFP bullet.

I’ve loaded .32 ACP for about 15 years now, for a pair of Walther PP pistols, an FEG APK7S and a Beretta Model 81.

.32 ACP has some unique eccentricities. Chamber dimensions vary. Walther PP and Beretta pistols tend to have tight chambers, while FEG chamber dimensions are pretty liberal (in both .380 ACP and .32 ACP).

European loaded .32 ACP / 7.65 Browning ammo is normally loaded with .308-309” bullets into brass with fairly thick brass at the case mouth. In contrast American loaded .380 ACP ammo generally uses .310-311” loaded into cases with comparatively thin walls at the mouth.

.32 ACP cast bullets run .312-313” and will *usually* work ok in The thinner walled US made brass, provided the chamber and leade are not too tight. The problems really start when you load a .311-313” bullet into European brass and try to shoot it in a tight chambered pistol.

If you load .32 ACP for tight chambered pistols, don’t want to continually sort your brass and want to use cast bullets, post sizing the loaded rounds works fine. I use a Lee Factory Crimp die intended for .32 S&W Long and .32 H&R, but with a spacer installed to allow it to work with the shorter .32 ACP. You can also use a .32 ACP sizing die with the decapping pin/expander ball assembly removed. Just adjust it so it sizes the finished round just enough to drop into the chamber on your snuggest chambered pistol.

Load wise, .32 ACP generally functions best and delivers best accuracy at the upper end of charge weights. I’ve had good results with Berry’s 71 gr plated bullets, as well as Rimrock 78 gr RN and 75 gr FP bullets for range loads and Hornady’s 60 gr XTP expands reliably as long as you have enough barrel length to get at least 1000 fps.

I’ve found a max load of both Red Dot and Bullseye give good results with all of the above.

For self defense loads however, PB produces excellent results with the Hornady XTP, but it was discontinued several years ago so when the few pounds I have are gone, that’ll be it. The good news is that at .32 ACP charge weights that day is still about 8500 rounds away.

The 32 Auto load in the Lyman manual uses a 75gr LRN bullet Lyman mold #311252 and they list an OAL of .975".

Is it possible my you over-crimping which could cause the case to bulge so it may not plunk?

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SWCA #3437

I may be over crimping, but I'm using a taper crimp die.

Try this, readjust your crimp so that you only remove the bell put in the case and see if it plunks. If it does then add crimp in very small increments until you can put moderate pressure on the bullet pushing against your bench and when you can't set back the bullet, stop there. That will be your proper crimp. Give that a try and give us a report. I truly hope it's as simple as that to fix.

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SWCA #3437

Life will be easier if you match factory bullet weight and velocity .

Where a bullet impacts is directly related to weight and velocity ....
Change any of these and POI changes.
The box of factory ammo will give you the bullet weight ... Match It .
Now it's simple to work up a load that matches the velocity and have a load where POI is the same .
You may have to try a couple powders to find " The Load" ... but just do a little experimenting .
Gary

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After considering your suggestions I decided the problem was in my final crimp. I'm loading on a Dillon 450, mixed dies with RCBS taper crimp in the final stage. Bullseye powder, mixed brass, Rimrock RNFP 75gn bullets and CCI SP primers. I do bullet seating in the third stage with 4th being final crimp only.

This morning I tried multiple, at least a dozen, settings on the depth and taper crimp trying to get a dummy round to pass the plunk test with the barrel removed from the pistol, all failed. Looking at my dies available I decided to try a RCBS 32 S&W long sizing die with the decaping rod removed. At 0.930" OAL they were passing the plunk test. The bullets also passed the push test without setting deeper in the case. I think it's the shape of the bullet not the case dimension keeping longer OAL from working in this instance.

I loaded up a dozen with 1.8 gn of BE and a dozen with 2.0 gn of BE seated 0.93" OAL using the sizing die as a crimp die. At 25' they both shot close to point POA with the 2.0 being a a little better. By close to POA the 2.0 BE group centered about 1" low and 1" left@ 25', close enough I can work with. So far no rim lock.

Thanks for the help and suggestions.

I disagree with part of this and I'll explain why. It's my belief that the purpose of a taper crimp is to remove the remaining flare from the belling step. It isn't to help hold the bullet. Roll crimps, which preceded taper crimps, do help hold bullets in place. When straight walled semi auto cartridges were developed, the term taper crimp came about because the operation (not the purpose) was similar to the roll crimp. The word crimp leads most people to believe that it should help hold the bullet. Instead, it's simply a misnomer. A better word would be debelling or something to that effect.

When reloading straight walled semi auto cartridges, the case mouths should belled just enough to allow the bullets to seat. Any more than that and you're just removing case wall tension that holds the bullet in place. After the bullets are seated, there should be plenty of case wall tension to prevent the bullet from setting back. If not, then the case is sized too much or the bullet is too small in diameter relative to the thickness of the case. Don't attempt to solve such a problem by applying more taper crimp than is necessary to debell the case. Instead, figure out what the problem is. When you get to the taper crimp step, simply turn the die down enough to remove all the flare from the debelling step. Less than that and it can cause feeding issues. More than that and all you're doing is crushing the cartridge. Brass springs back more than bullets, so you might even be lessening the case wall tension by turning your taper crimp die down too much.

As for the Lee Factory Crimp die for straight walled pistol cartridges, I believe that it's simply a poor solution to improper reloading. I think the Lee Factory Crimp die for bottle necked rifle cartridges is great for it's purpose, but that's another subject. The names are similar though.

All this said, if what you do works for you then you can't argue with success. I'm just sharing an important thing that I learned over the past 25+ years of reloading. Also note that I only load jacketed or plated bullets.