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ocelott
10-24-2011, 12:42 AM
I have a question for those of you that have Quick loads.

I'm loading a cast PB boolit with an average hardness of BHN 18 in 38 special brass for my Marlin 1894c with cci SP primers to an oal 1.520"

I am using 10.0gr of Alliant 2400 atm - I am getting decent accuracy, about 3/4" at 50 yards.

Where am I looking at pressure wise and would it be safe to push the load a little.

I do not have access to a chrony - so I am looking carefully for overpressure signs. So far the brass is showing no signs of excessive pressure.

fecmech
10-24-2011, 10:34 AM
That's an old .38 spl load that was listed many years ago in the Lyman manual. It's a dirty load that leaves a lot of unburned powder but it's not high pressure IMO for your Marlin. Just a WAG would be 18-20Kpsi.

Larry Gibson
10-24-2011, 11:55 AM
Where am I looking at pressure wise and would it be safe to push the load a little.

ocelott

You don't give the weight of the bullet?

This is a reprint of a post I made a while back on 2400 in the .38 SPL. Not SWAG'd psi's here but actually measured. Maybe it will help you.


Couple days ago I ran a test of Alliant 2400 in the 38 SPL under a 358477 bullet of 150 gr. Loads ranged from 8 gr to 13.5 gr (100% loading density). I used 10 shot strings measuring the velocity and pressure with the Oehler m43. Test gun was a Contender with 7.94" barrel. Cases were R-P, primers WSPs, alloy was WWs +2% tin sized at .360 and lubed with Javelina. The bullets were seated to an OAL of 1.485 (crimp groove) and a heavy roll crimp applied.

All the loads from 8 to 12.5 gr exhibited "reasonable" accuracy (would have been ok if a revolver but was pretty poor for this Contenderwith a 2.5X scope). The ES for each of those loads was very poor ranging from just over 100 fps to 345 fps with the 10 gr load. There were 2-3 very low inconsistent velocities in each test string from 8 to 12.5 gr of 2400. A heavier bullet would probably help with ignition consistency. The ES of the psi also varied to excess. The 11 gr load MAP was 20,300 psi(M43) which is max for .38 +P loads. Problem was that is an average psi and 4 shots exceeded that psi with one shot at 25,000 psi(m43). That is definately into .357 Magnum psi range.

The 2400 did not start to burn consistently under this bullet until 13 gr was reached. At 13 gr the MAP was 27,100 psi(M43) which is more than several factory .357 loads I've measured. The 13.5 load produced a MAP of 28,100 psi(M43) with an excellent ES of only 200 psi. The velocity was 1516 fps. Years ago I used that very load under the 358156 in 38 SPL cases in a Colt Trooper (service revolver with OSP) and a Ruger BH with excellent accuracy.

I would say that 9.5 gr 2400 under a 150 gr cast bullet is about max for standard .38 SPL loads. However the inconsistent ignition would lead me to a more suitable powder. However in the 357 using 2400 under 150 170 gr cast bullets has proven it's worth there.

FYI; the following 357 Magnum factory loads were also tested when the .38 SPLs were tested in the same Contender barrel;

Win 125 JHP; 28,200 psi
Rem 158 LSWC; 25,100 psi
Rem 110 JHP; 24,400 psi
Federal 158 LSWC; 28,500 psi
S&W 158 LSWC; 29,200 psi
Win 158 LSWC Lubaloy; 30,200 psi
Federal 110 JHP; 23,400 psi

Larry Gibson

fecmech
10-24-2011, 08:11 PM
My bad! I've got to change my brand of coffee or something, for some reason I thought I read a 158 gr. bullet.

ocelott
10-25-2011, 02:36 AM
I do apologize - The cast boolit is 180gr.

Cap'n Morgan
10-25-2011, 03:25 PM
According to Quick Load, the pressure is close to 30.000 psi, depending on the actual seating depth. Nothing alarming in a modern gun, but it is right up there with the 357 mag pressure and way above the 17.000 psi SAAMI Max load for 38spl.

ocelott
10-25-2011, 04:31 PM
According to Quick Load, the pressure is close to 30.000 psi, depending on the actual seating depth. Nothing alarming in a modern gun, but it is right up there with the 357 mag pressure and way above the 17.000 psi SAAMI Max load for 38spl.

The depth in the case is 0.430" +/- .001

An as I mentioned earlier these are loaded for my Marlin 1894C, This way with my 18" barrel I can load 10+1 - it gives me one more round in the tube.

What was the estimated velocity according to QL?

BTW - Thank you

NHlever
10-26-2011, 01:05 PM
QuickLoad doesn't list a 180 grain cast boolit, but the velocity out of a carbine with a jacketed bullet of that weight is about 1425 fps. I've never tried it, and don't know if it makes sense to, but going to 11 grains of H-110 will cut that pressure down to 18000 + and give you about 1200 fps according to QL. That is right at the max of .38 Special + P loads, but that is also with a jacketed bullet, so you are on your own there.

Cap'n Morgan
10-26-2011, 01:25 PM
Too bad Norma doesn't make their R123 powder anymore; 9 gr would give 1310 fps at 17.000 psi and 10.8 would clock 1540 fps at 30.000 psi.

jazzman251
11-24-2011, 09:50 AM
I do apologize - The cast boolit is 180gr.

I don't know the pressure, but I shoot 11.5gr of 2400 in a 357 mag case in mine and it's pretty hot. I'd be careful if I were you. You might want to measure some cases and see what the expansion is and keep an eye on the primer pockets.

hicard
11-26-2011, 11:20 AM
You are way over pressure with that load. ( approx. 33000+ psi )

excess650
11-26-2011, 11:48 AM
My old 1894c seems to like the 185gr Saeco #354 GC over 12.5 Alliant 2400 in magnum cases. The guy I bought another 1894CP from used 13.5gr under the 358429 with no leading, but again, in 357 cases.