finding the right load

T

trazman

Guest
hello, i am quite new to reloading. I would like to start reloading match ammo, but i dont know where to start...

I ve found theright bullet for my twist, i have 100 new brass and now i dont know where to begin...

i dont know for C.O.L. how far from the lands,which powder, which primer and how to experiment...

I thought to buy hodgdon h1000 and hornady a-max 208gr is it a good combination for 300 win mag or what do you suggest?
 
I am not sure what to say. Do you mean you have never loaded before? Do you have a reloading book of any kind?

You can start with reading this... http://www.6mmbr.com/jgcaseprep.html

I tested 7 powders in my latest 300 Win Mag and the H1000 was my final choice. But, those results vary so it may not be for you.
 
trazman

I think most folks use a Fed 210 primer, not the 215 magnum in the 300 win mag. I'm guessing that RL 22 would be the most popular powder choice with H 4831 second followed by RL 25 and H1000. Some shooters use 4350 (IMR or H) with very good results. I've always used H 4831 but I think the others would keep me just as happy.

I'd start with a square land mark on the bullet and increase powder charge on a single case until you loose the primer pocket. Alternately you can measure case head expansion to read pressure. 0.002" case head expansion on a mag case should be considered an indication of max pressure. Be aware that as you shoot a case multiple times it work hardens the head. If you started at say for example 67 grains of H 4831 and worked up at half grain at a time you might reach a total case head expansion of 0.002 at 72 grains and a loose primer pocket at 72.5gr. But on a virgin case that hasn't been work hardened by multiple firings, a single shot at 72gr would ruin the primer pocket. So if you developed a max pressure load that you liked in cases shot several times and then loaded it in virgin cases you might end up buying more brass and backing the load down to save your new, new brass from an early death.

Once you've got a max load at a square jam you can back the charge down and look for minimum vertical at 200 or 300 yards range. Testing long range loads at 100 yds won't tell you as much and farther than 300 adds noise to your results. Then start backing the bullet out of the throat 0.005" at a time to further refine your load.

As your barrel ages and the throat advances you'll need to seat your bullets out longer and increase the powder charge slightly to maintain best accuracy. On a 300 win mag you might experience the throat advancing 0.005" after 100-150 rounds and want to increase the powder charge a tenth or two when you adjust your seating depth. By comparison, a 6.5-284 would show about twice as much throat erosion per shot. A chronograph will help you find and restore the velocity you lost to throat erosion and that will get you back the accuracy you want until the barrel tanks at 2000-3000 rounds

There are more good choices for 30 cal long range match bullets than any other bore size so if you don't get the results you want with the A-Max's then try one or more of the other bullets mentioned above.

Good Luck

Greg
 
Greg thank you very much I will consider this.

Can you tell me also how much same loads shoot to see the accuracy... let say 2 or 3 groups of 5 shoots or how much?

And also are better loads with powder which uses more space in the case or with powder which uses less space?
 
tazman,

A group can't get smaller with more shots, so if the first two shots don't show something promising and there is no other explanation (wind puff or gun handling) you can move on without pounding three more shots just for the heck of it. As you refine your opinion of what's going to work with two and three shot groups you can increase to five shot groups. Five shot groups are still not statistically valid but the objective is to get the rifle shooting near its potential before we wear it out or run out of money for components and have nothing left to shoot in matches, not scientific proof of the absolute ultimate load which changes a tiny amount with each shot as the barrel is consumed anyway.

In short range benchrest with small cases, high load density is shown to be an important contributor to top accuracy while charge uniformity is lower on the list. Short range competitors quite happily and successfully dump charges straight from the measure into a case. Conversely, the larger, often much larger cases used in long range benchrest seem to be less responsive to load density but demand absolute consistency in charge weight. Long range shooters find greater success by weighing each charge, some of them to the nearest kernel of powder, plus or minus 0.2 grain. Part of this difference is due to the more consistent metering of the powders used in short range but part of it is not. Very low velocity extreme spread is an important indicator for long range accuracy but not so much in short range.

The 300 Ackley (300 Weatherby Improved) is a very well established and popular chamber for 1K competition that has low load density regardless of chosen powder. Probably as many competitors find success with RL22 as do with the bulkier RL25. Bob Rosen and I think Danny Brooks use 4350 in the 300 Win Mag to great effect and this choice leaves a lot more space in the case than other, slower powder choices will. In the early days of 600 yd IBS, I set a couple of single target records with Varget in a 6-250 improved. Varget is "too fast" for that loading and left lots of room in the case. Point is, don't worry about load density at 1K. Its about tenth on a list of three things that are crucial for good results.

Pick a powder and bullet (which you have done) and get that working for you.

Greg
 
I would have another question...

How often is it recommended clean the barrel each group or three or when??

And also is it good to wait the barrel to cool down durring testing ammo or it doesn`t affekt the group...
 
trazman,

If you clean much during load development you'll never get good info. It takes a clean barrel 4 to 5 shots to reach full velocity and point of impact. First shot in a clean barrel will record about 40 fps slow and hit about a foot low at 1K yards. I shoot 40 to 50 shots before cleaning when developing loads. About half that in competition. If you're loading at the range for load development your barrel won't get hot.
 
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