Speer Plinkers

[waterman]

I just found a couple of boxes of Speer 100 grain "Plinkers" in the mess left after the Dec. 20, 2022 and Jan 1, 2023 earthquakes. I want to find a load that will shoot them accurately (?) at 25 and 50 yards. All that with a desired MV about 2000 fps.

I have a barrel with an internal problem. It's a Remington 03A3 4-groove barrel. When slugged, one pair mikes at .308, the other at .3085. Last week I tried this at 100 yards, iron sights, with a load of known accuracy using Sierra Matchkings at about 2200 fps, my latter day version of the pre-war International Match load. Fired 10 shots into a big piece of paper while adjusting sights. Could only account for 9 holes. My spotter said he saw sand from one hit very high on the dune that is our backstop. That wasn't operator error.

I want to make some further investigations, but I don't want to blast my way through all my expensive Matchkings and beat up my shoulder while doing it. I have eight .30 cal rifles: 2 Krags and a High Wall in .30-40, 3 1903 Springfield military rifles (a real 1903, a Remington 1903A1, and the suspect 03A3) and a Buffalo Newton (with ratchet rifling) in .30-06, an 1899 Savage in .30-30 and another in .303 Savage. I propose firing 5 shots from each rifle, off sandbags, at 25 yards. Then, if necessary, doing the same thing again at 50 yards. My thinking is that if the 03A3 is really sending bullets flying, it should be evident when comparing 2 groups with groups from each of the other rifles.

Any ideas?

[FredC]

Waterman,
You probably saw the earlier discussion of plinkers in this thread.
http://www.kragcollectorsassociation.co ... 922#p44922
I think I made a note of Phil Sharpe's recommended load for 30/40 with Hercules Unique was about 16 grains. It would have been slower than my dad's load of 20 grains in 30-06. I will look for that note in the garage when I think about it.

The SR4759 in CarbonOutlaw's manual I have no experience with. it could be wonderfully better than Unique. No clue.

At 1800 to 2000 feet per second plinkers expand very well on small game. Tin cans do not care what load you hit them with. I would expect the SR4759 to be as easy
and pleasant to shoot as the same velocity as Unique.

[butlersrangers]

Speer .30-06 reloading data is viewable online and they provide 'reduced loads' for various bullet weights.

Some of these loads use IMR-4759, which is unfortunately a powder that is no longer manufactured.
(Accurate 5744 may be an alternative powder. It is reported to burn dirty).

I have had pleasant results using Hornady 100 grain 1/2 jacket .30 cal. and Sierra 100 grain jacketed .30 cal. bullets in reduced-load .30-40 cartridges.

The .30-06 cartridge case has a lot more capacity than the .30-40 case. I wish more manufacturers would develop reduced load data. Such rounds can be very accurate and useful at 50 to 100 yards.

BTW - At 100 yards, my 100 grain 1/2 jacket Hornady .30-40 reduced-loads grouped eight inches from where full-power 180 grain loads centered, (which was my point of aim).

[waterman]

Thank you for sending me back to the other discussion. 26 grains of IMR-4198 seems a place to start. I'll back it off by 2 grains (to 24.0 for the Krag case) because I'm using 100 grain Plinkers instead of the heavier and heavier jacketed 110 grain bullets. I'll go up and down with powder weights to adjust for case volume between the .30-30 and .303 Savage cases and the .30-06 cases.

I've always been bemused by the gun scribes and the guys who gin up loading manuals. For years, the classic mid-range load for the .30-06 was the 173 grain gov't bullet bought from the DCM and 36.4 grains of HiVel #2. It gave 2200 fps, and generated about 29,000 psi pressure. HiVel #2 was a double base powder and (IIRC) went away back in the late 1960s. Phil Sharpe listed an equivalent load, same bullet, but with 38.8 grains of IMR-3031, at about the same 2200 fps velocity and generating about 29,000 psi pressure.

That was always my test load in the '06 case. When there were no more 173 grain M1 bullets, I switched to 168 grain Matchkings. For the Krag case, I reduced the load to 34.4 grains IMR 3031. Those are way under the starting loads with almost any loading manual, but they work pretty well. I've used the 34.4 grains load in my Uberti High Wall 30-40, iron sights (tang rear and post front), in a 1,045 yard gong shoot, all the way across a windy canyon. Shooting 10 shots at a 6 foot steel gong. 6 audible hits out of 10 shots.

[waterman]

I like Krags a lot, but I'm really a single shot guy, with cast bullets and light loads of smokeless. SR 4759 is my version of unobtanium. I hoard any of it that I have. It doesn't work well in modern powder measures but almost works in my Belding & Mull. IMR 4227 is a fine grained powder that will deliver almost 4759 accuracy and without leaving unburned powder in your barrel. It's my choice for a lot of light loads.

I've also been fascinated by those old Winchester "Self-Loading rifles. New 2400 powder (Alliant?) is much more powerful and much faster than the same stuff made years ago by Hercules. The old "standard" load for the .401 WSL was 23.3 grains of 2400 and a 250 grain jacketed bullet. That generated 50,000 psi, but it was what made my 1910 Winchester work as intended. About 10 years back, I bought a new container of 2400 and tried the same load. First shot slammed the breechblock back & blew fire out of the ejection port. Breechblock sprung back so hard that it caught the case as it was being ejected, bent the case and jammed it sideways into the action.

That 1910 Winchester is only a bit bigger than a WW2 GI carbine, but weighs as much as a Garand. Shooting the thing is an experience. So is a trip to the dentist.