Adjusting charge weight vs seating depth

[NASIROKLA]

Im a total newbie to reloading. I just loaded my first batch of handloads. I have a 111 30-06 i was having trouble getting to shoot worth a darn with factory ammo. I was pleasantly surprised with the results. 150 ballistic tips started low and worked up to noslers website listed max charges of imr 4350 and imr 4064. 59.0 and 52.0 g respectively. Groups tightened up as the charge weight increased. Both shot the best under max charge. Both under an inch at 100. So my quesion is- should i try and increase maybe another .2 g to see if it tightens up more, maybe decrease by .2? Or should i just start tinkering with seating depth. Right now they are seated .020 off the lands. Thanks

[Three44s]

Work down from your manual's max if you have reached that level. Use as small an increment of reduction as your patience allows for best results.

As to changing seating depth, always treat that as a "different" load and reduce your charge weight to the start and work back up watching for sweet spots.

You have to watch for pressure spikes when you alter your seating depth. Close to the lands is one area of concern and the other is caused by reducing case volume materially through deeper and deeper seating depths. In effect you are reducing case volume.

[darkker]

You didn't mention any velocity, if you don't have a chronograph, you should NEVER match book Max loads!
Look at the warning in every manual, and on the side of your powder, it says "drop loads 10% when switching lots". So you better take their word that there are normal burning rate differences on the order of 10%. The book data doesn't tell you the lot number used, so do not assume you have the same lot.
Watch velocities. Assuming you have the and length barrel, a production fire arm had greater than the SAAMI min spec test barrels used. So you will have slightly slower velocities, when suddenly you match book velocities; you have gone over pressure.

Personally I've never had a rifle that "needed" fooling with jump, unless I was working on ultra long range targets. Never met a rifle/bullet that wouldn't shoot well from a standard 0.032" jump to the lands.

[savgebolt]

so darkker,,,,, are you saying that while working up loads ,,, for accuracy ,,, less than 300 yds ,,,,22-250,,,,, bullet weight less than 69 gr,, that distance to lands is irrelevant ,,,,,,, also i read somewhere that with h4895 powerder , and other extruded powders one should load
by volume , not weight , can you help with that also

[earl39]

I can answer that somewhat. X amount of pressure = X amount of velocity plain and simple. How you get to that pressure can be done in a number of ways.

[darkker]

No, my point was sitting to only 300-ish yards, bullet weight is totally irrelevant. Uber match bullets, Vs. Sp flat base; will have all but identical flight paths that short.
For jump, any bullet weight, use the 32nd.

[NASIROKLA]

Ok so i backed off the charge weights a liitle at a time. The 4350 still shot the best at max charge, in fact max charge was the only one that shot well. Imr 4064 tighted up a bit and shot the best when backed down just .2g and shot about 3/4" 3 shot group. Reloader 19 shot about 3/4" as well but havent had a chance to fine tune it. As far as seating at 1/32, are you saying that for safety's sake or just a general rule for accuracy? Thanks again

[243LPR]

Is this a hunting round or just for range? Are you single loading or feeding from the magazine? Makes a difference in OAL.

[daniel87]

Look into the ladder method and the optimal charge weight when You research them you will see how to determine what and when to change charge vs bullet seat depth