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working up a load from scratch
joshmb1982
Member Posts: 8,228 ✭✭
ive been set up for loading for about a year now. while ive worked through a crap load of brass i havent done much loading. ive fired off a few of my reloads but am not sure where to start with developing a load for a particular rifle.
where do you start first? say in a 308. keep the cartridge oal the same and just vary your powder volume until you find something that works and then play with the oal some and try and get it dialed in better?
or do you load a few batches the same to start and figure out what oal your rifle likes first, and then go on to find the powder/bullet combo that works best?
where do you start first? say in a 308. keep the cartridge oal the same and just vary your powder volume until you find something that works and then play with the oal some and try and get it dialed in better?
or do you load a few batches the same to start and figure out what oal your rifle likes first, and then go on to find the powder/bullet combo that works best?
Comments
1 Start with brass prep. Size it to fit MY chamber. To do this, I take the firing pin out of the bolt and close the bolt on an empty casing. It is a "feel" thing to know when it's right. The bolt should not just fall down on it's own, but shouldn't take more than slight finger pressure to close it.
2 I figure out what seat depth will have the bullet just barely touching the lands in THOSE cases with THOSE bullets. This is a trial and error process done seating a bullet on empty case with no powder or primer. You need a magnifying glass to see the marks the lands leaves on the bullet. If they're rectangular in shape, bullet is seated too long. You want them to be very small square marks. Some brillo pad works well as an "eraser" to rub the marks off of the bullet so you can adjust and try again without using a ton of bullets. When I find the "sweet spot" I use this as my starting point and write the OAL in permanent marker on the case
3 Primers. You probably already know what primers you're going to use and although they will produce different results, I'll say use what you've got and skip this step for now.
4 Bullet choice. Whatever you have on hand, save to use for foulers. Buy Bergers. Don't argue. Just trust me. I argued. I have seen the light. I buy Bergers now.
5 Powder charge. Consulting a manual of your choice, you will see that there is a min and a max load for the powder and bullet weight you are using. I've found that the higher the velocity, the better the accuracy. Of course, that is only good up to a certain point. Therefore, I never start at the min load. I figure out what the center point is between the min and max and I usually start there. Then increase a little and see what it does. Then do it again. When you see groups tighten up, start increasing in SMALL amounts like .5 grains at a time. When groups open back up, back the powder back down accordingly. You may find it necessary to adjust OAL .001" while playing with powder if you're not getting good results. I know what you're thinking: .001" Really? Is that really necessary? Does it really matter that much? Answer: YES. .001" Difference in seating depth can mean the difference between groups and patterns!
I'm sure I'm forgetting some of the other things I do but right now I can't remember them. Of course, the time and effort you are willing to put into loading will all depend on your personal definition of "Accuracy" If you want to shoot minute of bad guy or hunt deer, etc. Then factory ammo will work just fine for the most part. If you want to shoot groups, you have to put the time in to beat the factory.
THE first thing to do is to make a firm decision about what is "good enough" for you. Do keep it realistic; deciding you want 4,000 fps and one-hole groups at 500 yards is fantasy, not practical goal-setting.
If you don't get close to your goals using proven "book" loads and techniques, you need to either alter your goals or try to find where the basic problem lies. Only after you DO get close should you begin to tweak things like seating depth.
Start at the book overall cartridge length, or whatever will fit and feed from your guns magazine if that happens to be shorter. Pick a proven powder and begin with START loads. Shoot five-shot groups and split the spread between START and MAX into five equal load increments. Whichever seems to shoot the smallest group, try a powder charge a bit either side of the best one and then pick the best of those three. If the result meets your accuracy goal, you can either stop or try adjusting the seating depth a wee bit deeper once or twice to see if there is again any improvement. Record all that info.
If you decide to try another bullet or another powder, start over as above. It's as simple as that.
And is it a hunting rifle or competition target rifle?
Big game hunting rifles normally can be little less accurate than a target competition rifle when reloading!
Josh, there are a gazillion arcane and tedious things some guys do to work up a load - most of them probably unnecessary at best or counter-productive at worst. Using every benchrest trick known to man is utterly useless with a factory rifle.
THE first thing to do is to make a firm decision about what is "good enough" for you. Do keep it realistic; deciding you want 4,000 fps and one-hole groups at 500 yards is fantasy, not practical goal-setting.
If you don't get close to your goals using proven "book" loads and techniques, you need to either alter your goals or try to find where the basic problem lies. Only after you DO get close should you begin to tweak things like seating depth.
Start at the book overall cartridge length, or whatever will fit and feed from your guns magazine if that happens to be shorter. Pick a proven powder and begin with START loads. Shoot five-shot groups and split the spread between START and MAX into five equal load increments. Whichever seems to shoot the smallest group, try a powder charge a bit either side of the best one and then pick the best of those three. If the result meets your accuracy goal, you can either stop or try adjusting the seating depth a wee bit deeper once or twice to see if there is again any improvement. Record all that info.
If you decide to try another bullet or another powder, start over as above. It's as simple as that.
+1 sound advice