Powder lot question 300 Win Mag w/TTSX & RL 22

[RobStar]

I'm new to reloading and I've just worked through my first two batches of loads on my 300 Win Mag shooting 180gr TTSX and came up with a .54 MOA load in my lightweight sporter rifle using Reloader 22.

Of course being new I only bought one pound to start and it's nearly gone. Duh!

All I've been able to find are lots with one number difference in the lot I started with.

Before asking here I've read and researched and found volumes on lot differences.

Should I expect all the work I did with the first pound of powder to be wasted and need to start over? Is there a generally accepted process for reworking loads with close-numbered powder lots?

Thanks! ~Robert

 

[Bbear]

I wouldn't say it was wasted. Just that with a different lot you will need to back off a bit and work back up.
If your load was say, 56 gr of the RL22 with Lot 'A', with Lot 'B', I'd back off 2 grains and work back up (provided the lesser load is still more than minimum for your round). If the max load was 60 grains, you could find that with Lot 'B' your new load may be 55.5 or 56.5 or even 59 grains.
Basically, you'll have one more trip to the range. And, what's the problem there?

With a new to me rifle/round, if I don't have a powder that works, I'll do like you did - buy 1 lb of powder to try. If that powder works, I'll go back and either buy multiple pounds of the same lot # or buy an 8 lb-er. I'll then do as I said earlier, back off a bit and re-run the loads and find what load THAT Lot # takes to get me back where I was.

 

[kraky]

What I do in a situation like that as I run down to the gun shop and see if there are lot numbers close to what I had. And I make sure there are several there..... I buy 1 pound and run home and proof a load..... if it's confirmed that it's right next door to or equal to what I had I run right back to the gun shop and buy another 2 pounds!

 

[Lefty7mmstw]

rl22 is uniform enough you ought to be fine, but as the other poster said you need to back off a couple of grains for a few shots to be sure. I'd load a group of 5 at two grains under and a group at your current charge weight and fire the mild one first.
Make sure you get enough of the same lot for a couple of hundred rounds now that you know the load works.

 

[PGJPJ]

To be honest, for my standard hunting rifle (not specifically precision/long range stuff), I just don't worry about it. For those, I'm using book loads (mostly from my Nosler manual), which will tend to be conservative with the charge.

If you found max pressure with your rifle, and that is what you are shooting with, then it would be a very good idea to back off a bit when changing lots. Get the old chronograph out, and try to tinker with your charge till you get back to that velocity which worked for you before.

 

[RobStar]

No I'm not at max pressure at all and the load that groups best also has the best spread of only 11 FPS.