.40 in the wind

[ewc]

Shot the .40 again today. Temp was 45 or so, but the wind was 15-20 with gusting to 30 - a great day to shoot .

Cows were @ my 100 and 200 targets, so I shot at 300 yards all day (anyone care to guess where this is going?)

Because of the wind, I thought I could at least gather data for speed.

Shot the 200 sst, Fed 209a primer and 2 dry wonder wads. Chrono was about 8' and I swabbed with a dry patch between shots (I think this may help with my gun).

First off was a guess of Steve's - 12/78 of 4759/H4350. Shot 2838, 2842, and 2773. Slow, but a 5.5" group at 300.

Next I tried a new powder (powder # 10 with the .40 and me) - RL-17.

It compares favorably to H4350 in burn rate. I think it to be a tad slower than H4350 in the .40. I started at 12/71 and went up to 12/75.

12/71 went 2747, 2706, and 2758 for a 7" group.
12/73 went 2767, 2721, and 2773 for a 7" group
12/75 went 2809, 2759, and 2780 for a sub-4" group

Checked the chrono with my 7-08 load (43 Varget and 140NBT) and it shot 2,800 - right where it normally does.

OAL (12 4759 + primary = powder column only)=

RL-17-
71 = 2.520"
73 = 2.582"
75 = 2.627"

H4350-
78 = 2.774"

I guess I'm going to bump my primer charge next time out. If I can find a solid 2900, I'll be done. I don't think my gun will get to 3000. I could be wrong, but 2900 and accurate is just as good.

FWIW, with 12 shots at 300 (with the wind), I would have killed 12 deer - easy as pie.

[Richard]

ewc.........sounds like you are on the right track!
Richard

[matthewj]

well i finally took the plunge and tried some similar duplex loads. I Did NOT have any 4359 or H4350 so what i used was below both with a 200 Gr Hornady FMJ pistol bullet.

N-110 10 gr / IMR4350 70 Grains cronoed 2655,2662, one no read on chrono ..It shot right at about an inch at 100 yrds

nxt and last load was
N110 12 gr / 75 gr IMR4350 chronoed at 2930, 2936, 2938
and shot about 3/4 inch at 100 yrds, 2 touching and one just off from the other two. I Think with the way this shoots at Low Temp, (it was only about 10 degrees here this morning) I will leave that load alone alone and probably not look for much more speed.

[ewc]

I don't know Richard- maybe / maybe not I had higher hopes for RL-17. Its a cool powder - smaller extruded than 4350. I'm definately going to give it another go or two-

accurateshooter.wordpress.com/2008/02/12/alliant-releases-new-reloder-17-powder/

I think bumping my primer by 1/2-1 grain increments is my next chore.

Rl-15, RL-17, and H4350 are where I'm going to focus.

-Judd

[DBinNY]

ewc, that's very impressive under those conditions (or any other for that matter). I think it also demonstrates that velocity is an important component of accuracy at long range. If you get the bullet there faster it has less time for wind to screw it up.

[sw]

Shooting in the wind isn't much fun, nor the cold. As we've discussed in PMs, we are going down the same track, except for my not having RL-17. I still think my final load will be between 10-12 VV-110 under 75-78 H-4350. Seems like VV-110 gives more speed g for g as a booster than 4759.

[rbinar]

8-)Judd I did some pressure calculations for the data you supplied and got these results for the three loads given. I allowed for a 23.35" barrel and a non recessed plug. I figured a powder volume of .3242, .3322, and .3435 cubic inch. That in turn gives a case size of 82, 84 and 86 grains of water (I rounded slightly but very little). I also gave average speeds of 2740, 2765, and 2785fps
Pressure(CUP) 40766.549
Expansion Ratio ® 9.256
W 82.000
F2 2.029
K1 17955434.738
K2 1.537
K3 677.012
Pressure(CUP) 41011.014
Expansion Ratio ® 9.004
W 84.000
F2 1.983
K1 18296417.294
K2 1.507
K3 672.351
Pressure(CUP) 40948.617
Expansion Ratio ® 8.877
W 86.000
F2 1.958
K1 18763594.949
K2 1.478
K3 677.433

The results all work out the very near 41kcup. The one variable I’m concerned with is what is referred to as F2. Perhaps if Mark has a comment he might provide direction or at least where information exist on the net about this subject. I once had a very nice web source with tables for F2 but can’t seem to find it now.

Another problem I have is the measurements you provide suggest a bulk density for RL22 to be greater than 1.0 it should be between .92 and .95 This might be a dimension problem. My suggestions are first make sure I’m using good data for your barrel. If I am then you should see better results for a slightly faster load. I think that for an 85 grain powder charge best 200 grain bullet speed should be near (but less than) 2900fps at 60 degrees F.

Those who use N110 should not be surprised that it will seem faster than 4759. N110 has an extremely high bulk density, whereas 4759 is an exact opposite. This lowers the expansion for all loads and would result in higher pressure even if both powders burn at the same speed.

[Dave W]

Jan 24, 2009 23:48:35 GMT -5 sw said:

Seems like VV-110 gives more speed g for g as a booster than 4759.

I have been saying that for 3 years. The last lot of N110 I bought is 175fps faster than the same load of 4759 at 43gr.

[dave d.]

:)great work judd.those groups are very good for those conditions.i love reading .40 stuff i should get out and shoot mine again but not untill hunting season is over.

[ewc]

Jan 25, 2009 1:30:36 GMT -5 rbinar said:

Another problem I have is the measurements you provide suggest a bulk density for RL22 to be greater than 1.0 it should be between .92 and .95 This might be a dimension problem. My suggestions are first make sure I’m using good data for your barrel. If I am then you should see better results for a slightly faster load. I think that for an 85 grain powder charge best 200 grain bullet speed should be near (but less than) 2900fps at 60 degrees F.

Those who use N110 should not be surprised that it will seem faster than 4759. N110 has an extremely high bulk density, whereas 4759 is an exact opposite. This lowers the expansion for all loads and would result in higher pressure even if both powders burn at the same speed.

RB-

When I shot RL-22 on Thursday, I did not remember my dial caliper, so I marked oal on a notepad and measured with the dial caliper when I got home. This may be part of the error. Yesterday, I marked my barrel empty with electrical tape on a rod- then measurements where taken with the caliper. Bullet and ww oal was then subtracted.

My barrel (empty) measures 23 1/16".

I can get my hands on N110 if you think it will help. I just have a ton of the old metal can 4759.

Also, the RL-17 I would think is much denser than the H4350. It was designed for packing wsm cases and providing more speed.

I'll double check some measurements today before I clean things.

Thank you for the help-

[chuck41]

Very interesting. Just got home last night after two weeks and am anxious to the the 40 out with some 410 wads and 357 bullets. Unfortunately the weather here turned really cold yesterday (at least for us cold weather southern wimps). Perhaps later in the week.

[rbinar]

8-)Judd

I don't have any RL17 but I do have H4350 and RL22 and both of those I measured for Bulk density. Both are less than 1.0 with 4350 being about .98 and RL22 being a little less than .95

However all this means that the pressure estimates might be a little high compared to perfect dimensions. That's not a big problem what you have to look out for is low estimates that give a false sense of security.

What I'm getting at is I think all these loads might show even better results with a slight speed increase (about 100fps or less) compared to present levels.

I'd also say you're at a number of shots where the vent can be used for help here. How many total shots do you have at these load levels and what liner wear have you seen if any?