300 WM handloading concerns

severed

Private
Minuteman
Feb 29, 2012
29
0
41
Graham, NC
Having a new rifle built and had some questions about powder and charges.
From the reading I have done, i have narrowed my powder choices down to RL-22 and H-1000. I plan on shooting either the 208 A-max or one of the Berger offerings, depending on what the rifle likes. For the A-Max, there is not powder load data for H-1000 in the Hornady manual. So how do I know where to start?
Also, for all the other rifles and handguns I load for, I have always just loaded to the OAL listed in the manual. But with this rifle I will be adjusting the seating depth according to the throat of the barrel. So how will this change my starting and max load? I mostly load 5.56 for my M4 and .45 acp for my several handguns and have never had to worry about seating depth and all this is new to me.
Thanks
Robert
 
Re: 300 WM handloading concerns

I have tried many a combo in my 300 and have talked to others that shoot them as well.
Some common things we have all found are,...
Do not use a mag primer. A 210 match is about as good as it gets.
Re-22 an Re-25 work very well.
Bullet weight depends on how far you want to throw them.
Bullet selection, nothing beats a target Berger, jammed into the lands.
I'm running
Prepped Win brass
210M's
79.7 grs of Re-25
190 Berger VLD at 3.642 OAL
11.27 twist, Rock, w/3K down the tube and the last 5 rd group shot was witnessed by ASM1 and his son Chase. 615yds from the hood of my truck 2.125" ctr to ctr and I'm no shooter at all.

I've shot about every combo, but this one out does them all. I've never shot Bergers in a match before as if they won't feed from the weapon they are of no use to me. The Wyatt DBM system has been a blessing, now I can shoot the Berger's and not worry about OAL an feeding at all.
 
Re: 300 WM handloading concerns

Books are a starting point, the best to start with is Lyman. They are not lawyer ed up as bad as others.
Another thing to remember is as you increase OAL (everything else the same) "Most Always" peak pressure drops.
The Book OAL for the 300 will put a lot of the bullet into the case, an that's OK for most things, but not if your reaching far with her. I've the Navy's A19 chamber in mine as it has to eat dirt, an still go bang.
For yours just pick your bullet, seat her where the mfg says to start, (jump or no jump), then start your loading process down 6-8% in powder weight an work up a 1/2 gr at a time, until you reach pressure. Most of the time you will find two spots she likes one low an one high. Then you can fine tune w/OAL if you want.
 
Re: 300 WM handloading concerns

Instead of starting with a book OAL, I usually find the OAL where my bullet hits the lands and start my loads at .02 off the lands.

First, find a powder charge your rifle likes, then play with seating depth.

You can buy a special tool to find where the lands are in your rifle, or you can take a piece of sized brass, and cut slits in the neck with a dremel or hacksaw, do some research on using this method to find OAL.

My best adice to you would be to read all the handloading stickey's in this forum, I believe there are four or five of them. I've found them to be extremely helpful.
 
Re: 300 WM handloading concerns

First, go look at the 300 win mag reload data thread here. You should find H1000/208 Amax load data from others. Second, you can measure bullet seating depth either by COAL or ogive length. I prefer the latter but always confirm I am in the ballpark with what other folks have determined for COAL. As BMK noted, seat around .02 off the lands. I use Forster Micrometer seating dies.
 
Re: 300 WM handloading concerns

Well, gunfighter may not have answered the question specifically, but it still looks to be useful information. I do not see that what he offered went against everything I have read, or know to be factual?

The poster states that he is leaning towards R-22 and H1000 and an AMx or Berger and it is apparent, that this project is not completed therefore he should be able to weigh additional input. I would, if it were me, keep my options open for the time being.

One thing, and I have been shooting a 300WM for close to 40 years, is that I have always used the Winchester LR primer and avoided mag primers. Of course, my handloading is strictly for hunting applications and I have never used a bullet over 180 grains. That being said; H4831 is all I have ever needed, which also does not answer the question, but you may file it away for future reference.

And, this reminds me of a certain build. I was sure of what I wanted and what I got. However, once the shooting started, I found that I needed to readjust my plan and switch to a heavier bullet within the limitations of the twist, which I could do nothing about, after the fact.

Good luck. BB
 
Re: 300 WM handloading concerns

Hornady will supply you with load data for the 208 AMAX, if youbwant to wait I have the data at home and I'll post the figures up later on. Otherwise just email them and they will shoot you a .pdf.
 
Re: 300 WM handloading concerns

Email Berger for load data for their bullets. The reloading sticky here suggests starting OAL into or very near the lands and start at your lowest charge. This way if you started with the minimum or book OAl and found a charge near max that works well, you won't run into pressure problems by playing with OAL. Read the sticky, the author explains it better than I can paraphrase.
 
Re: 300 WM handloading concerns

 I'm also developing loads for the Berger hybrid targets and the Hornady 208 Amax and 225 bt. I have re22 and h1000. I start my load with the bullet touching the lands and work up to find the charge that gives me good results without showing pressure signs. Then move the bullet away from the lands, shorter coal, in .003" increments looking for improvement or worsening. If you don't have data for a specific powder and bullet combo, you can use a similar or heavier bullet's data to get you in the ball park.

Here's data from Berger for the 215 and 230 gr hybrids: good luck!


300 Winchester Magnum
Bullet Powder Start Load Approximate Start Velocity Max Load  Approximate Max Velocity  Fill Ratio
215 Grain VIHT N165 65.0 2530 68.3 2650 95.0%
215 Grain RE-22 66.0 2653 69.6 2790 95.0%
215 Grain IMR 7828 SSC 66.5 2674 69.9 2809 94.0%
215 Grain RE - 25 68.5 2669 72.0 2795 100.0%
215 Grain H1000 70.5 2632 74.0 2772 103.0%
215 Grain NORMA MRP 2 70.0 2645 73.8 2793 102.0%
215 Grain Ramshot Magnum 72.0 2667 76.0 2830 93.0%
215 Grain RETUMBO 74.0 2686 77.9 2836 107.0%
215 Grain AA 3100 65.5 2571 69.0 2698 101.0%
215 Grain VIHT N160 63.0 2521 66.0 2630 95.0%
215 Grain IMR 4831 60.5 2589 63.5 2693 91.0%
215 Grain H4831 SC 65.0 2598 68.7 2740 94.0%
215 Grain IMR 4350 60.5 2583 63.5 2690 88.0%
215 Grain VIHT N170 71.0 2575 75.0 2669 105.0%
215 Grain AA MAGPRO 69.5 2657 73.4 2812 95.0%
215 Grain NORMA MRP   66.0 2647 69.5 2780 92.0%
 
 
300 Winchester Magnum
Bullet Powder Start Load Approximate Start Velocity Max Load  Approximate Max Velocity  Fill Ratio
230 Grain VIHT N165 61.5 2382 68.2 2617 96.0%
230 Grain RE-22 61.0 2443 67.9 2700 94.0%
230 Grain IMR 7828 ssc 61.0 2440 68.1 2715 93.0%
230 Grain RE - 25 63.5 2466 70.8 2723 99.0%
230 Grain H1000 65.5 2425 72.9 2711 103.0%
230 Grain NORMA MRP 2 65.5 2459 72.8 2736 102.0%
230 Grain Ramshot Magnum 66.5 2439 74.1 2738 97.0%
230 Grain RETUMBO 69.0 2489 76.5 2764 106.0%
230 Grain AA XMR 3100 60.5 2367 67.3 2607 99.0%
230 Grain VIHT N160 59.5 2370 66.1 2606 96.0%
230 Grain IMR 4831 56.0 2398 62.0 2603 90.0%
230 Grain H4831 SC 60.0 2388 66.9 2647 96.0%
230 Grain IMR 4350 55.5 2373 61.9 2597 87.0%
230 Grain VIHT N170 67.5 2374 74.8 2649 106.0%
230 Grain MAGPRO 64.5 2451 71.6 2724 94.0%
230 Grain NORMA MRP 61.5 2457 68.6 2720 92.0%
230 Grain RE - 50 76.5 2440 85.1