reduced load data

[moooose102]

i found reduced load data for my .300 win mag somewhere, using imr sr4759. but now i cant find it. i looked through all my books, and it is not in there, so i must have gotten it from the internet someplace. can anybody steer me in the right direction? being forgetfull bites!

 

[MMCSRET]

Look in older speer manuals 8,9,10,11 maybe.

 

[dirtman]

Yeah there is some info in speer # 10 pages 249-251
100 grn plinker at 19.0 grns of sr4759= 1626 muz vel
23.grns of sr4759 = 1975 muz vel
with 165 grn bul .. 25. grns of sr4759 =1736 muz vel..
29.o grns of sr4759 = 2000 muz vel.

they also list 150 grn bul & 110 bul

good luck

 

[mkl]

In addition to the above, Speer #11 gives:

1) 110 Gr. Spire point, SR4759: Start = 21.0 Gr. for 1718 fps. -- Max = 25.0 Gr. for 2024 fps.

2) 150 Gr. any shape, SR4759: Start = 24.0 Gr. for 1743 fps. -- Max = 28.0 Gr. for 2028 fps.

I don't have a clue why the heavier bullet wants more powder, but the above is what Speer #11 shows. All of the above data is for jacketed bullets.

 

[rcmodel]

The heavier bullet needs more powder to get the required 1,700+ velocity.
Longer bullet = more bearing surface = more friction.

Below that velocity level, a jacketed rifle bullet is liable to stick in the bore.

rcmodel

 

[mkl]

rcmodel: Thanks for the info. Makes good sense. I had never heard the 1,700+ rule before.

You may have saved me from sticking a bullet. Going to try some 85 grain 30-30 loads in a couple of weeks, and no data exists for a bullet that light.

I'll have a chronograph and be sure to keep them above 1.700 fps. They are jacketed.

 

[moooose102]

rcmodel, i by no means mean any dis respect, but where did you get this from? and how is it figured? i don't know all that much about reloading, i admit it, but it seems to me that if the bullet leaves the barrel at 700 ft/sec, IT LEFT THE BARREL, so why would it need another 1000 ft/sec? please explain?! i do not understand. is it a theroretical calculation of some sort?

 

[dirtman]

mooose102 rc is right... i should have mentioned the bottom loads were red lined do not load anything slower.... those loads are very close to 1700 ft per sec. muz vel.

 

[rcmodel]

There is no 1,700 FPS rule for every bullet weight.

But long heavy .30 bullets like Moose102 is trying to download have a much longer bearing surface, and much more bore friction then the 85 .30 grain bullets MKL is going to try.

For him, 1,500 fps might always clear the bore in any rifle or barrel length.

For the ones Moose102 is using, it appears the bullet companys testing has determined 1,700 FPS is as low as you can go and still be safe in any firearm.

Moose102's rifle might have a very fine bore, and be perfectly safe at 1,200, but Unkle Harveys rechambered 1917 Enfield .300 mag might not have as smooth a bore & might stick a bullet at 1,200 FPS.

The reduced load data has to be safe in any .300 mag, and it appears 1,700 is a minimum safe velocity as determined by Speers ballistic lab.

rcmodel

 

[moooose102]

thanks for the clarification rc. as usual, you are full of good, helping advice.