Range Report 300 WM external velocites

[winxp_man]

Ok so I went out yesterday the 6th of May, and shot 50 various loads of 220 SMK and 208 A-Max. Here are the numbers and they kinda pissed me off.

Alt- 151 sea level.
Temp ranged from 79.9* to 83* when I was done shooting for the day.
Humidity started at 31.8% and came down to 25%
Bar Pressure started at 29.920 and ended at 29.870

220 SMK
76.0 H1000
Winchester Brass @ 2.610 (New case capacity was 89.48)
CCI 250 Mag Primer
COAL from Ogive 2.880 (Which should = 3.450 COAL for the 220 SMK that is)

2729
2748
2769
2766
2759

76.5 H1000

2802
2729
2724
2826
2826

77.0 H1000

2789
2770
2773
2785
2794

This is the same setup with Retumbo powder.

78.0 Retumbo

2836
2823
2807
2845
2800

78.5 Retumbo

2800
2807
2806
2822
2830

I dont get the variation in the numbers ? I wonder if the primer had something to do with it. I just got some Federal 215M maybe this will give me better consistent numbers.

Here I changed the bullet to the Hornady 208 A-Max COAL from the ogive was 2.880 but from the tip it was about 3.650

76.5 H1000

2842
2803
2845
2835
2838

77.0 H1000

2825
2846
2818
2845
2833

These loads are with Retumbo but same 208 A-Max

79.00 Retumbo

2958
2838
2968
2884
2990

79.5 Retumbo (These loads all had a pretty bad sticky bolt)

2950
2869
2909
2913

Again not very consistent with FPS at all. I will try all these loads again with Federal 215M primers and see what happens.

 

[varmint slayer]

Re: 300 WM external velocites

What are you using to weigh your powder charges?

 

[winxp_man]

Re: 300 WM external velocites

Im using a RCBS Charge master with out the dispenser. Its all loaded with lee scoop cups. I recently loaded some .308 with RL-15 and super consistent. Max spread was 16 FPS in .308 stuff. I know my scale is fine cause Every about 10 rounds I use the RCBS scale weights.

 

[jrob300]

Re: 300 WM external velocites

I had to anneal my Winchester brass to get any kind of consistency. It gave me fits from the git-go, but settled down once annealed.

John

 

[winxp_man]

Re: 300 WM external velocites

I will do just that thanks for the input John

Regards Aron-

 

[jwoolf]

Re: 300 WM external velocites

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jrob300</div><div class="ubbcode-body">I had to anneal my Winchester brass to get any kind of consistency. It gave me fits from the git-go, but settled down once annealed.

John </div></div>

+1 on that one.

After 2 firings, they HAVE to be annealed to keep any accuracy at all in my own rifle. Inconsistant neck tension is not your friend.

At about 1100ft above sea level, I settled on 73.5gr of H1000 under the amax and, I'm pushing them about 2820fps out of my 26" barrel but, I'm kissing the lands so OAL is around 3.62 so, that probably explains the lighter charge weight for my loading.

I may go hotter to find the higher accuracy node but right now, 1000yds is all I'm shooting and for that, this load is more than fine. So this way, the brass lasts forever, the barrel lasts longer and, there wouldn't be a noticable difference at 1000yds anyway.

 

[winxp_man]

Re: 300 WM external velocites

Thanks for the info jwoolf. I even have to anneal some .308 win cases also.


Regards Aron-

 

[jwoolf]

Re: 300 WM external velocites

I'm fairly new to trying to get bench rest accuracy out of a rifle and, I've only done it for a couple of years now but, I've found that brass prep has done the most for accuracy improvement than anything else.

I've started annealing, turning necks, deburring flash holes etc. and, wow... no more flyers. LOL

It sure is a labor of love though... You have to love shooting do put all the effort into it.

I have to spend quite a bit of time in the garage this week. I'm going out to a friend's deer lease to see if we can make the ol' 300wm make some hits at a mile next weekend! I've got to do a lot of loading!!!!

 

[winxp_man]

Re: 300 WM external velocites

I prep the shit out of my brass

Just never got around to annealing. I'm going to start though. I never really thought about neck tension but now I see the pure effect if its not done.


Aron-

 

[30/50]

Re: 300 WM external velocites

++1 on the annealing

 

[winxp_man]

Re: 300 WM external velocites

Well I just finished reloading the next 50 rounds for testing. I will post results when I get a chance. I even got to anneal the cases so we will see what happens with this batch.



Aron-