Hey guys,

So last night I loaded up some ammo for a 300 WM. I made a total of 60 rounds. I had three different bullets, Nosler Ballistic 150, Nosler Silver 168 and Nosler Partition 180. I had several powders to choose from, IMR 4831, H4895, RE22 and IMR 7828. I also had Winchester and CCI Primers in both LR and Mag.

I decided to do them all with the same powder, IMR 4831 and I made 20 rounds with each bullet type and I used the CCI LR primers.

How do you guys go about testing? What would you try first? Upping the powder? Different powder? Different primer?

All rounds were made with the starting charge.

Tom

The first thing I do is decide what bullet I want to try. I then pick a powder and a primer. I usually start at minimum charge and work my way up to maximum carefully, looking for signs of excess pressure. All with the same bullet, powder and primer. Cases are all FL resized and trimmed. Primer pockets cleaned. I usually start with bullet seating about .020 off lands, if it will fit into magazine. If you are lucky enough to get a good group or two with your first combination, I load it up again to see if it will repeat itself. Document all you have done. On your targets, it's a good idea to write the load combination, date, yardage, weather and air temp. If you don't get any groupings that are satisfactory to you, I would change powders and start again with the same bullet. If you run the gamut of powders and can't get it to shoot, you probably should try a different bullet, and start the procedure all over again. I've had to do this often. Once I get a good, REPEATABLE load worked up, I then try it at different temperatures over the course of time to see if it will still shoot the same. Loads worked up in the summer may not shoot the same in November or December, and may need a bit of tinkering. This is basically how I go about it. I'm sure others on here will be glad to give you their procedures too,and perhaps some of the more technical aspects that I didn't mention and the reasons why. Just MY way........

Well, you did the same thing I did starting out. But I regretted it. I found a load I liked, and had to disassemble the rest. I knew back then I wanted a partition to work for me. So I gave it a try, then changed powder, gave it a try.

for each bullet combo, you need to start out 10% below max value. They all can behave differently. I have taken a leap of faith with large capacity cases and moved in 2gr increments. See if anything is promising. But I had alot of experience with that particular firearms and knew they generally didnt' build up pressure very fast. Also has experience with the bullets and knew how they usually build up pressure. There are a few bullets to be careful with, barnes, anything barnes, failsafes, TBBC, Scirrocos.

The problem with all those loads, is usually I become fatigued after 30 rounds of shooting from most guns. Not the kick so much as mental concentration goes down, and you start making judgement calls later in the day when you tired. Also, make sure you clean all the copper/fouling out when changing to a different bullet/load, so you have a unbiased opinion.

I myself, usually load up 6 of each load with the same bullet. I shoot a group of 3 for each load at 100 yards. I then use the other 3 for each load for 200-300 yards. If my results match I know I have something to work with.

"There are a few bullets to be careful with, barnes, anything barnes, failsafes, TBBC, Scirrocos." Why?

If I'm trying to develop very accurate loads that are also good for hunting should I be using premium bullets? Should I maybe stick with cheaper bullets until I find the right amount of powder to put in the case and then switche to a higher end bullet?

With all the combinations to shoot I'm starting to think about trying to save some money in the process.

Tom

Barnes, failsafes, etc, have a solid shank. They build pressure much faster than other bullets. Lets say you shoot 96gr of H1000 with 180gr sierra in a RUM. No pressure signs and seems safe. Try that with a 180gr TBBC, and you might blow the gun up and best case, you just locked the brass up in teh chamber. Scirrocos have a very soft very thick jacket that also builds up pressure faster than most.

You need to load with what you want to hunt with. Every bullet/load combo is different. I can get 53gr of IMR4350 and 130gr gamekings to shoot great in my 270win, but switching to 130gr bullistic tips, I need to drop it to 51gr. In fact, I had to change powders to 4064 to get it to shoot accurately.

Here is what I do. With a caliber, I have a particular bullet in mind I desire to shoot. For example, I picked up a 300win mag a few weeks ago. I want this gun to shoot 180gr accubonds. First choice. So I look at all teh data and what powder I have on hand, and decide RL22 is an appropiate first choice. I try it, if it doesn't work, I will try 4350, if that don't work, I will change over to 165gr to see what it does. Have a bullet in mind you want to work for you.

Statjunk, that's a lot of ammo for trial purposes. I sort of agree with BC only I load 10 round of each and shoot 5 shot groups. Also, in order to keep the results of the load fair, I clean the rifle after every 5 shot group to eliminate the varible of a fouled barrel affecting the group and let the barrel cool down between groups and alternate the different loads for each 5 shots. You definately don't want to go shooting 20 rounds or more, especially with the 300 WM. That barrel will get pretty hot and if you have a bedding issue you will see stringing as the barrel heats up.
As for selecting poweders, I refer to several manuals and check velocities. I try to initially use a powder that will give me the most MV and fills the case to just below the neck. I try to avoid powders that don't fill the case enough or result in a compressed charge. Once I find a load that is consistantly accurate, I play with it by increasing, decreasing the charge, changing powders and, if possible, the OAL.
You seem enthusiastic about reloading but take your time. Its better to go out and shoot 20 consistant shots in a session than to blow out those 60 rounds as fast as possible. It should take you the better part of the day to fire off those 60 if it is done properly. Remember to write everthing down either on the target or separate paper. (Load, group size, range weather conditions, etc.) And remember, one tight group doesn't mean that's the best load - what you need is repeatability)
Big - I have a load for you with IMR4064 using 180 gr Nosler Accubonds. I will post it here later when I get home.

Bigcountry: that load Nosler 180 gr Accubond, 60.0 gr of IMR4064, Rem 9 1/2M primer. OAL 3.390". I've played with IMR4350, 7828, 4831 and RL22 but for some reason this rifle likes the faster 4064 powder with this bullet.

Yea, bronk, I have found 4064 to do better most of the time in 270's bad news is I can never break 3K FPS with it. But can with 4831 or 4350. I never thought of using 4064 for 300win mag. But then again I shoot 4350 for 7mm-08 and it works.

Where do primers fit in the grand scheme of things? How do I know if I need a mag primer? One book that I have says use standard LR primers and another says Mag. Which one?

Tom

I generally go with 215M primers for magnums. Butyou should start byusing what the load data calls for. You will get a feel for what you like and don't.

If you are using a fast powder like 4350 or faster, I might try a 210 primer.