need help from the pros

[azleadburner]

I went to the range to work up some loads for my 300um. rem lss, factory 26 barrel w/ muzzle break approx 80 rounds to date. using 200 gr accubonds with retumbo.
averaged from 3 shot groups
82 grains 2650
82.5 2698
83 2759
83.5 2833
84 2939
84.5 2763
85 2951
85.5 2823
86 2844
as you can see it kind of fell on its face and I dont know why. all rounds were loaded individually on a digital scale, I rechecked by loading some at 85 grains and went back to chrony, they avr 2750.
Im lost, is the bullet exiting before the powder is burned up? I could use some suggestions
Fred

 

[elkfirst]

I had similar inconsistency when using my digital scale. I pulled all rounds that I had loaded and went back to my balance scale...problem solved. How much does one have to spend to get a good digital? The accuracy of 0.1 gr that they claim is bullsh*t.

 

[hoghound]

AZ, looks like to me you ain't stuffin enough powder in her. Pour the meat to her about 94gr. and watch her smile at 3100fps. Another tack driving load is 91.5 of RL-25, It was giving me 3263,3267,3261 on that perticular day and temperature. It did in fact shoot a 1 hole group at 300 yds. but be warned, this powder is very very very temp sensitive in this caliber. At least it is at 165 feet above sea level.

 

[azleadburner]

the max load in the book for retumbo is 86 for a 200 gr bullet, just to clairify you are saying go to 94?

 

[hoghound]

Check out page20. There is some pics of a gong I beat the snot out of with 210bergers and Richard's 210 wildcats. I was shooting 94gr. of Retumbo going 3100fps. Only thing I do not like about Retumbo if you try and strech it past that you will see the velocity start to go down the primer pockets seem to open up. I liked 91.5gr. of H-1000. It was not all that fast 3025's but it was consistant and the temp didn't seem to bother it. If you really want to smoke one out there shoot 97gr. of H-1000 behind a Berger 185vld at 3400fps. It will roll a 125lb. hog at 500+ yards no problem.

 

[hoghound]

Also look at page21. Later Tim

 

[B Jordan]

[ QUOTE ]
the max load in the book for retumbo is 86 for a 200 gr bullet, just to clairify you are saying go to 94?




[/ QUOTE ] i have seen max in books from 86gr to 92gr of retumbo behind a 200gr bullet i can shoot about 95gr before the primer pockets start opening up but i get the best accuracy about 93 grs with the AB's out of a 31" 5c broughton runs right at 3220 fps for me

 

[bailey1474]

More powder is the ticket!!!

 

[remingtonman_25_06]

Use 94-95g retumbo, or 92g h1000. Both give right at 3200fps and .5-.75 moa. I personally like h1000.

 

[Gatsby378]

What MV were you expecting from these loads? And, what group size were you getting?

 

[jwp475]

Lifted from the Hogdon web site:

200 GR. BAR XFB(Starting Loads)
DIA. .308" COL: 3.555"
US 869 96.0 2834 58,000 PSI
H50BMG 92.0 2767 56,100 PSI
H870 101.0 2931 56,700 PSI
RETUMBO 81.0 2852 56,200 PSI
H1000 80.0 2767 57,400 PSI

200 GR. BAR XFB(Maximum Loads)
DIA. .308" COL: 3.555"
US 869 100.0 2919 61,800 PSI
H50BMG 98.0C 2910 63,100 PSI
H870 104.0 3028 61,300 PSI
RETUMBO 86.0 2988 62,800 PSI
H1000 83.0 2850 62,800 PSI

220 GR. NOS PART(Starting Loads)
DIA. .308" COL: 3.530"
US 869 97.0 2758 49,500 PSI
H50BMG 95.0 2699 54,000 PSI
H870 101.0 2818 54,800 PSI
RETUMBO 84.0 2800 56,600 PSI
H1000 83.0 2704 54,500 PSI

220 GR. NOS PART(Maximum Loads)
DIA. .308" COL: 3.530"
US 869 101.0 2875 55,200 PSI
H50BMG 100.5C 2850 62,500 PSI
H870 104.0 2956 62,400 PSI
RETUMBO 89.0 2905 61,900 PSI
H1000 89.0 2863 63,500 PSI
Notice that the max load for the 220 grain partion is 3 grains more than the 200.
The 200 grain is the Barnes Original X and will make highe pressure fast. 95 Grains of Retumbo and a 200 Grain Accubond is a fairly common load in the 300 RUM

http://www.hodgdon.com/data/rifle/300rem.php

 

[hoghound]

Here are the links I was Refering to./ubbthreads/images/graemlins/grin.gif

http://longrangehunting.com/ubbthreads/s...;page=19#102012

http://longrangehunting.com/ubbthreads/s...;page=20#109795

 

[jmden]

I'd agree with the 'more powder' crowd. I've heard of a few folks that have gone back to high quality scales after using digitals for awhile. To each his own...

Here's what I've found out of the same rifle with some accurizing done to it, but minus the brake.

Retumbo did not do well for me with the 200AB's. Might just be the batch I got, but it seemed like it was quick to see pressure signs. I think I was around 92g and was surprised to see the pressure signs I was seeing. Maybe 3025fps. I was so dissapointed in the pressure signs vs. speed I was getting, I started looking to other combinations.

I did develop a very good load with Retumbo and the 180AB. With the Wyatt's box, I could seat them on the lands and with 96.3g Retubo, I was doing about 3285fps comfortably at about .4 MOA off the bench. I seemed to me that at least the batch of Retumbo I had was better suited to 180's in my rifle.

RL-25 with the 200g A-frame did OK for me. 94.4g at just about 3100fps.

Now I'm working up a load with Hodgdon's US869 and 200AB .010 off the lands--gotta like that Wyatt's box. I'm getting over 3200fps with 109.5g and seeing less pressure signs than I did with Retumbo at 92g. Turned off the high spots on the necks and just neck sizing so far. Off the bench at 100yds I've been in the .3s. This is far better accuracy that I had either with Retumbo or RL-25 and the 200AB.

Again, with the 180 and Retumbo, I did quite quickly find a fine load. But it seems almost like a waste to put a 180 down a 300RUM, so...