Subsonic .38/.357 Loads for Cowboy Rifles

[ke4sky]

Practical shooters know that handgun-caliber ammo which averages two inches or less at fifty yards over a series of 5-shot groups from a scoped rifle or test barrel is entirely satisfactory for field use, because that’s better than most people can shoot. When seeking dual-use ammo to feed your cowboy rifle and wheel gun, you only need one basic ammo that is more accurate than you can shoot with middle-aged eyes and iron sights.

“Traditional” standard velocity (not +P) .38 Special ammunition loaded with lead round nose, lead flat nose, or semi-wad cutter bullets feeds more smoothly from the lever guns and “carries’ up” better beyond 50 yards than target full wad cutters. I tested four factory .38 Special loads as benchmarks, then an assortment of factory swaged and cast wad cutter, lead round nose, lead flat nose and semi wad cutter bullets at 50 yards to see where they shook out.

Benchmarks included a good lot of Norma 158-gr. lead round nose and three batches of wad utters, an oldie, but goodie, and two new boxes, one was cheap, the other expensive. Of historical interest was “the last” of what the late LTC Ellis Lea described as “the best wadcutter Remington-Bridgeport ever made,” a souvenir from the 1960 Olympics. This ammo with Rem-UMC head stamp averaged 1.16” at 50 yards for ten consecutive 5-shot groups from my Green Mountain barrelled, Unertl-scoped BSA Cadet Martini used for ammo testing.

The Norma 158-grain lead, round nosed ammo was a mid-1980s batch which had established history in testing custom PPC revolvers. It performed exactly as expected from long experience, velocities averaging about 720 f.p.s. from a 2” snubbie, 800 f.p.s. from a 6” revolver and just under 1000 f.p.s. from the Cadet Martini, shooting round groups which averaged 1.6” at 50 yards from the Unertl-Scoped Martini.

Current production (new and expensive) Winchester wad cutter from Midway was disappointing. One group containing a keyhole which enlarged it to almost six inches, the best group was just under two inches and five targets averaged just over three inches. Cheaper Than Dirt’s imported Sellier & Bellot Czech stuff shot fairly well, averaging just two inches.

Of the factory swaged, hollow-based wadcutter component bullets sold for reloading only Remington’s averaged consistently less than 2” at fifty yards. The often recommended 2.8 grain charge of Bullseye averaged 1.8”, but increasing the charge slightly to 3 grains shrunk the average to an inch and a half. The Remington 158-gr. Lead SWC flat base of .358 diameter loaded to 1.45” overall with 3.5 grains of Bullseye shot just as well as good wadcutter reloads. Speer’s 158-gr. Lead Round nose with 3.5 grains of Bullseye was also a pleasant surprise, fully equaling my prized lot of Norma LRN.

So, knowing what factory loads and handloads with swaged bullets did, I tested traditional lead .38 Special loads with cast bullets so see how they measured up. Cast bullet loads included the Saeco #348 double-end, bevel-based wad cutter, the NEI #161A 190-gr. FN; and bullets cast from another NEI #161A four-cavity, which was shortened to remove the base band, producing a 150-grain flat-nosed cowboy slug.

The Saeco #348 double-ender, shot unsized, tumbled in Rooster Jacket and crimped in the crimp groove over 3.5 grains of Bullseye averaged 1.87.” Both light and heavy versions of the NEI #161A, loaded with the same lube and powder charge averaged an inch and a half at 50 yards, actually slightly better than the wad cutters. A couple shot holes with the 190-grain bullets showed slight yaw at 50 yards, so I increased the charge slightly to improve stability. A charge of 4.2 grains of Bullseye, crimping in the top lubricating groove in .38 Special cases at 1.55” overall length tested in the Unertl-scoped Martini averaged 0.87” with the largest group 1.07” and the smallest 0.61! @~&*% Now THAT got my attention! Hmmmmm....

I decided now that it was time to try .357 Magnum brass. Seating the 190-gr. NEI #161A in its normal crimp groove using .357 brass the cartridge OAL is 1.58”. A charge of 4 grains of Bullseye gave 1000 f.p.s. from the 24” Marlin Cowboy II and averaged under an inch and a half. Increasing the charge to 4.3 grains enlarged the average slightly, but it was still less than two inches. Increasing the charge to 4.5 grains increased velocity to 1080 fps, but enlarged groups. It was time for harder alloy.

I bought 190gr. LFN bullets from Hunter’s Supply which are of the same profile as NEI's #161A, but commercially cast from harder 92Pb-6Sb-2Sn "hardball" alloy. I also loaded Winchester 158-grain jacketed hollow points in new virgin Winchester cases, with WSP primers and 14.5 grains of #2400 because it was time for a jacketed .357 benchmark.

The Hunter’s Supply hard cast .358” diameter 190 LFNs with 4.3 grains of Bullseye averaged under an inch from the scoped BSA-Martini at 50 yards. Increasing the charge to 4.5 grains the harder alloy averaged 1.26”, almost exactly half what cast wheel weight metal bullets did when overdriven. Handloaded Winchester JHPs also averaged exactly an inch at fifty yards.

It was now time to go to 100 yards. I also took the best load and tested it again in the Marlin 1894 Cowboy II Limited with 2.5X Weaver scope. The Norma .38 Special 158-gr. LRN factory loads averaged 3” at 100 yards. Handloads with swaged lead round nose and semi-wad cutter ammo in .38 Special cases didn’t shoot as well, but did stay under 4 minutes of angle, having useful field utility.

The Hunter’s Supply cast 190 LFN of 92-6-2 alloy and sized .358 from Midway, with 4.3 grains of Bullseye in .357 cases averaged 2.18” in the BSA and 2.36” in the Marlin - not a statistically significant difference. When casting the NEI #191A from wheel weights I got comparable results as long as I kept velocities with the softer wheel weight alloy subsonic. I settled on 3.5 grains of Bullseye in .38 cases and from 4.0 grains in .357 cases based upon accuracy results.

Supersonic cast bullet .357 loads do not group as well at 100 yards as the slower loads. This is because the faster projectiles are subjected to transonic buffeting as their velocity decays below the speed of sound. So my advice is not to magnum-ize it, but keep it slow, accurate and quiet. A good working velocity range is from 950 to 1050 f.p.s. so there is no “crack” to disturb the neighbors. A big flat-nosed bullet is effective on groundhogs, wild turkey and larger edible critters raiding your garden. Bon appettit!

[AJMD429]

Fascinating info. Once I load up some .44's, my next project is .357's, and I had been planning on just that - two loads to keep it simple; one which would give just under Mach I from my longest rifle, for best accuracy I hope (all else being equal, which of course it isn't). The other hot-rodded for when 4 minutes of angle isn't a big deal, but I want a bit more punch, as in for deer @ 75 yards.

I'm not even sure if I need the second load, to be honest, but it is always fun to have some 'hot' loads.

[w30wcf]

Ed,
Thank you for a very informative article. Just curious about the 1960 Olympic .38 Special wadcutter ammunition. What was the overall cartridge length?

Thank you,
w30wcf

[w30wcf]

btt

[Ben_Rumson]

Great post.. Thanks for the great info...It's already printed out!

[JerryB]

Thank's for the good load data. I just saved it and will be trying some.

[KT-45]

I've been using 5.5 grains of Unique with a .358, 146 grain, LRNFP bullet for the Lovely and Talented Miss Randi's CAS guns for years. It's accurate in both of her revolvers and her leverguns.

5.5 grains of Unique is somewhere in the ".38+P" arena.

It works for us.

[Lefty Dude]

Alliant has Cowboy loads listed on there Web site. I use several of there loads. The one Unique load I like is with .357 cases, 158 gr. RNFP and 3.9 gr. of unique 750fps. The other is with 38 cases 125gr. RNFP, 3.2 gr. of American Select 675fps. These are out of handguns, add 200fps for rifles.

All my sub loads are very accurate. I also subload 44-40, & 44 special.

[Griff]

For years I've loaded 3.5grs of PB with a WW 158gr. RNBB from a Saeco 391 4 cavity mold for my wife's and son's CAS ammo. Ain't the cleanest burning round, but accuracy has been unsurpassed. In their iron-sighted Rossis, sub 1-½" has been the norm @ 50yds. And my son (with his youthful eyesight) has been a constant source of amazement @ 200 yards with this little round.

[Texican]

Practical shooters know that handgun-caliber ammo which averages two inches or less at fifty yards over a series of 5-shot groups from a scoped rifle or test barrel is entirely satisfactory for field use, because that’s better than most people can shoot. When seeking dual-use ammo to feed your cowboy rifle and wheel gun, you only need one basic ammo that is more accurate than you can shoot with middle-aged eyes and iron sights.

The second statement is mostly true, but...

As I understand it: If the best you can personally shoot is 6" at 50 yds and your firearms's best is 4" at 50 yds, your groups could be as large as 10" across. It adds because the two 'error radii' can compound each other. Ex. your shot lands on the left outside of the 3" radius (personal best accuracy) from center and the firearm's accuracy limit (2" radius) chooses that shot to land left as well. I believe Whelen did quite a bit of study in this regard.

Of course in chance occurrences, the reverse can occur on occasion, where the firearm's (lack of true) accuracy can subtract from the shooter's error, leading to frustrating results of widely varying groups from target to target.

For some reason there are quite a few claims in the gunpress about 'suitable accuracy for cowboy action games'. CAS is still a target game and accurate is always better than not.

Just my two cents,

[colo native]

ke4sky


Great post..
I've used HuntersSupply pills for a lota years, probably since 1997 or so, and have had a lota good groups even up to 100meters with his 32-20 pill.
As to soft swadged pills, Starr (now out of business) made the best 148 hbwc ever, and a 158 was just as good, still have about 20 boxes of 500 of em...