32 H&R Mag Single Six Velocity Much Lower Than Predicted With Unique

[jonp]

Acme 100gr RNFP
New Starline Brass
S&B SP
2.5gr Unique
OAL 1.375 crimped in groove
32 H&R Ruger Single Six

I made 12 of the above loads yesterday and ran them over my chronograph. According to my Lymans #4 Cast Bullet Handbook a Saeco #326 using 2.5gr should have been about 800 fps. The OAL though is 1.305 vs my 1.375.

My avg velocity for my 12 shot string was 623 fps, well under the Saeco but my OAL was longer which could mean more space in the case, less pressure etc.

Anyone have a Saeco #326 and could give me the boolit OAL for comparison? Also, this is my first 32H&R and dealing with this small a straight wall case in this handgun (Single Six frame). Considering the velocity and almost no recoil, think I should bump up the load until I reach the expected velocity as max load with the 100gr is 892 with 14,800 C.U.P. using 2.7gr Unique. IE: increase powder weight until velocity target is reached paying attention to velocity spikes, primer condition etc. Not interested in hot rodding this gun, just increasing performance to listed.

Many reports of people turning their Single Six's into 327 Fed which are at 2x the pressure being in the 40,000 cup range vs the 15-20,000 of the 32 H&R so I should be OK?

Also an interesting note of Lyman vs Lee. The Lee book gives much different loadings often varying .5-1gr with higher or lower velocities to match. In my Blackhawks i'm not as concerned as long as pressure signs are fine but the Single Six is a much smaller frame and the brass also small so 1 gr is quite A difference.
The Alliant manual is different across the board with almost all loadings above either Lyman or Lee.
Any thoughts on this?

[Outpost75]

Your increase in overall cartridge length reduces load density and pressure. Your Unique charge is normal for a .32 S&W Long, not for an H&R Magnum. In your Single Six you can safely load 3.5 grains of Unique in .32 S&W Long brass or 4.5 grains in .32 H&R Magnum brass with your Saeco #326. Lyman keeps its loads light in deference to the H&R revolvers chambered for the .32 H&R Magnum, but its SAAMI MAP actually exceeds that of .38 Special +P and the Ruger Single Six, like the SP101, is a sturdy gun and you can prudently exceed the SAAMI MAP of 22,500 psi by about 20% with no issues.

I use 3.5 grains of Bullseye with Accurate 31-105T in mine.

[Wheelguns 1961]

I have loaded a 100gn swc from an accurate mold as high as 4.0gn with no pressure signs in my .32hrm S6. I didn’t chronograph it, but I have seen load data as high as 4.4. I have had a hard time finding a good shooting bullet in my S6. I have had the best results with dewc’s and bnwc’s of 98-100gn. I have no desire to hotrod mine either, as I also have a S7. I have been loading these wc’s over 2.5gn of bullseye.

[Larry Gibson]

Lyman used a 5" barrel in a Universal receiver.....that is a lot different test condition than your Ruger revolver. I get considerably higher velocities with the same 32 H&R load out of my Contender barrel than I get out of my Ruger 6" revolver. You're making an apples to oranges comparison of velocities.

[rintinglen]

2.5 grains of Unique is very light. Too light, in my view. IME, Unique runs best when loaded to 15,000 PSI or Higher. Your load would run maybe 12,500 PSI. I used 3.5 grains with a similar SWC from an LBT (IIRC) mold as well as with the RCBS 32-98 SWC for good to excellent results.

I take it you are using the Lyman 4th Edition Cast Bullet Handbook. In the case of the 32 H&R, the boolits not of Lyman origin are (Under) loaded to only about 3/4ths the pressure that the Lyman boolits are loaded to...

[Thumbcocker]

I load 4.0 of Unique with 100 grain rnfp boolits.

[jonp]

The book lists 2.7 as max so I thought I'd keep it under for a first trial. I just was not expecting it to be that different.

Lyman used a 5" barrel in a Universal receiver
Larry, I'm aware of this but was not expecting the results to be 30-40% off. I had not considered this in a small caliber pistol but is this type of variation from the test barrel to real world in a revolver standard? Seems awful high to me.

[Walks]

I tried light charges of UNIQUE, a long time ago. When RCBS first brought out the little DANDY powder measure.
For some reason I got uneven powder "throws" when using light charges of UNIQUE. I don't know if it was just that I needed to perfect a technique for throwing charges or something else.
But I've found that UNIQUE seems to throw erratic charges under 4.0grs.

Perhaps that's why My Family always used BULLSEYE for small charges in light loads.

I use what is listed as an overload by the HODGDON Data Center & LYMAN Cast Bullet Handbook #4.

It's a bit more then HODGDON lists for TiteGroup under a 100gr Lead Bullet. Accurate and my 5 1/2" SSM handles it easily. But I'm down to less then 100 SAECO #326 Bullets & no longer have the mold. Guess I'll have to use the LEE 93gr RN until I can find a new 100gr SWC mold. In the .32S&W Long, I use 2.0grs of TiteGroup.

These loads are safe in my guns, but may NOT be SAFE in yours.

[jonp]

Thanks for the replies. I'm just treading cautiously with my pair of new to me Single Six's. I have several kegs of Unique so thought I'd try some. With charges this low I will most likely switch to Bullseye or HP38 which meter better for me.

[Harry O]

Random notes.

1) Pretty much all of my .32 H&R Magnum firearms give lower velocity than what is published, including with factory loads. I did not know the details of how the numbers were arrived at, but suspected it was something like the pressure barrel noted here. I have chronoed several factory loads and use those velocities as a benchmark.
2) I don't go much by the exact amounts of powder listed in the manuals. I usually start with them and then work up to the velocity I get from factory loads. I have no proof, but I think that the pressure is probably not much more than the pressures for factory loads. I use those loads in most of my .32 Magnum guns.
3) I have two guns that I have gone considerably above factory loads. One is the Ruger Super-Single-Six. The other is the Ruger SP-101. I don't have pressure testing equipment, but I believe that the pressures for my handloads in those two guns is probably in the 28,000psi range (about the same as what Elmer Keith used in his .44 Special handloads without destroying too many guns). No problems with either one in any way, shape, or form. I have had the Single Action for over 25 years and the DA for about 10.
4) I have moved away from Unique because of the repeatability problems with meters mentioned above. I have found that HS-6 is about as forgiving as Unique, but meters MUCH better. You do need more grains of HS-6 to match the velocity of Unique, but that is not a major problem. Also, I often make little scoops out of fired .22LR cases and use them for loads that are less than 5 grains. With practice, scoops are as accurate as meters and are a lot quicker. Both Bullseye and HS-6 work great with scoops.

[Outpost75]

Can't speak specifically to .32 H&R Magnum, but in .38 Special firing standard pressure, lead-bullet 148-grain wadcutter or 158-grain lead SWC, the velocity difference between a 4" revolver built to Mean Assembly Tolerance with a barrel-cylinder gap of 0.005", is about 80 fps less than a 4" solid test barrel. This is not absolute and will vary depending upon the powder type and loading, but it is a good ballpark number.

Comparing .38 Special +P lead and +P+ jacketed HP service loads fired in a .357 chambered revolver and .357 chambered 4" solid test barrel the difference exceeded 100 fps. Firing .357 factory loads in revolver vs. solid test barrel the difference was similar.

Again, not absolute and I am relying on memory, for this testing was done back in early 1980s. The result of that testing was the development of a 2-piece "vented" test barrel in .357 which maintained a consistent 0.008" (Max. Assembly Tolerance) gap to simulate revolver conditions, which for a time became the industry standard for contract acceptance of .38 Special and .357 ammunition purposed for service use by the Federal government.

When the Federal alphabet soup agencies quit buying revolver ammo, the vented test barrel requirement went away and the ammo manufacturers all went back to solid test barrels, supposedly to reduce costs, but others say it was more likely to give inflated catalog velocity figures so that people wouldn't realize that the loads were being reduced concurrent with adoption of piezoelectric pressure measurements. There's an element of truth in that, but some LE loads which tested OK (not exceeding Industry +P standard by more than 15%) when using radial copper, but notably the US Treasury Q4070 loads of that era, were REALLY too hot, exceeding SAAMI MAP for +P by as much as 25% when more accurate peak pressures were measured.

Those Q-loads were very hard on K-frame S&W and were the impetus for development of the L-frame.

[Larry Gibson]

Chronographed Federal's 90 gr LSWC factory load out of my Ruger (original run) SS with 6 1/2" barrel (8" breach to muzzle) and out of my Contender 10" barrel (breach to muzzle. Ten shots out of each over Oehler 35P with start screen at 15' gave;

Contender; 1203 fps
Ruger SS; 1024 fps

That's 179 fps difference give a closed breach and 2 more inches of barrel vs the revolver.

[Outpost75]

Great data point! Thanks Larry.

A bit more difference than I would have guessed, but I'm not sure what powder they use in .32 H&R factory loads.
For a slower powder like WC630, HS7 or Power Pistol that seems on the money.

Curious if you've measured barrel-cylinder gap on your Ruger, is it larger than 0.006"?

[jonp]

Thanks for the data, Larry.
With your and others input i'm going to bump the Unique up but i"ll end up switching to HP38, Bullseye or something else that measures better at this level

[lawdog941]

I scoured the internet and this site, with all the suggested loads for my Single Six. In the end, I found 3.5 grains of Green Dot or HP-38 to be the most accurate. not top end, but I'm able to hit shotgun shells at 25 yds. Tried it at 50 yds, almost can't see the shells. That's with 100 RNFP also. Getting old bites...

[MtnGunner]

I really like accurate arms #7, meters very well and shoots great in the .32 mag for higher velocity loads.

[jonp]

The only accurate I've tried is 2230. Just not a line of powders I mess with for some reason.

[JoeJames]

I tried light charges of UNIQUE, a long time ago. When RCBS first brought out the little DANDY powder measure.
For some reason I got uneven powder "throws" when using light charges of UNIQUE. I don't know if it was just that I needed to perfect a technique for throwing charges or something else.
But I've found that UNIQUE seems to throw erratic charges under 4.0grs.

Perhaps that's why My Family always used BULLSEYE for small charges in light loads.

I use what is listed as an overload by the HODGDON Data Center & LYMAN Cast Bullet Handbook #4.

It's a bit more then HODGDON lists for TiteGroup under a 100gr Lead Bullet. Accurate and my 5 1/2" SSM handles it easily. But I'm down to less then 100 SAECO #326 Bullets & no longer have the mold. Guess I'll have to use the LEE 93gr RN until I can find a new 100gr SWC mold. In the .32S&W Long, I use 2.0grs of TiteGroup.

These loads are safe in my guns, but may NOT be SAFE in yours.I have decided that the most accurate and consistent 32S&W Long loads in my S&W 631 4", and my 1903 32 S&W Long Handejector 4" were those with Bullseye at 2.1 grains under a 98 grain lead SWC. In the 631 they were running 694, 681, and 689, and in the Handejector they were running 636, 681, and 684. I save Unique for medium to hot loads.

[Larry Gibson]

Great data point! Thanks Larry.......Curious if you've measured barrel-cylinder gap on your Ruger, is it larger than 0.006"?

Measured it this morning. Cylinder drags on .004 and .005 won't go in.

[Rodfac]

If your looking for a good bullet in a Ruger SS . 32 H&R, you might try one of Accurate Mold's #31-100R. I cast mine from ACWW+1% tin and size to 0.3115" for both of my guns. (A bird's head 4-5/8" bbl. & a 5-1/2" bbl. standard grip model). Neither leads whatsoever and both have throats that hover a might over 0.311". It's a great bullet for the .32 H&R, and I hope it'll work as well in my Smith 4th type hand ejector in .32-20.

Unique is my powder of choice with 4.0 grains being a particularly 'sweet' spot. Grouping is all that I could ask for; just over an inch with the longer bbl. and adjustable sighted gun, and a bit more with the bird's head. I've not chrono'd the load, but suspect around 1000+ fps from either based on research here on the forum.

For a day to day carry gun, doing chores here on the farm, either is a joy to carry and that combination of 100 gr. SWC & Unique is plenty for a trail type carry piece in KY.

Rod

[jonp]

With the comments here in mind in regards to the extra length of 1.375in using Acme 100gr SWC I switched to Bullseye and 2.8gr gave me an
avg 938.67fps and about 195 ft-lbs with PF at 93.

Recoil was very little, the load was clean with no pressure signs and the brass popped right out with minimal effort. I'm going to bump it up to 3.0grs which should have me at 1,000fps and if it groups then stop at that as my max with this boolit.

Next stop will be Promo with a similar load and hopefully I can find time to cast some Lee with my new mold this weekend and try those out.