How "important" are certain details when reloading?

[trophyhusband]

I'm about to work up an elk hunting round for my 300 H&H and this will be my first time reloading rifle rounds. I put "important" in quotes because it is such a subjective thing. By important, i mean, how much effect do certain details have on accuracy? While I want to improve in the long run, my current goal is to be able to hit the vitals on an elk from 400 yards. That means that for me, something that may give me a .1 MOA improvement may not be that important right now (although it will be in the future).

For bullets I have chosen 180gr Nosler partitions. I have always in the past bought factory ammo with that bullet for both my 300 and 30-06 and have been happy with the results so being new to this, I went with what I was familiar with.

For powder I chose IMR-4831and for primers I chose WLR's based on the Lyman Reloading Handbook, which used the same rifle I have for their testing.

My focus and my questions right now mainly concern the brass. Remember, this is in the context of my current goals. Just to quantify it, lets say that 1.25 MOA is acceptable for the time being. I know there are a lot of variables and that no one here can give exact numbers but I'm hoping for some ballpark figures or a little guidance as to what to focus on to start with.

Case length: The length of my brass varies from about 2.825 to 2.850. How much should I separate it, variations of .005? .010? .015?

Weight: I haven't weighed the brass yet so I don't know how much it varies, but at this level, how much variation in weight is acceptable?

Primer pocket: Do I need to get a primer pocket uniformer or will just cleaning them get me to my goal?

Flash hole: Should I bother de-burring the inside of the flash hole?

Jump to lands: For testing purposes I want to make up 3 or 4 different OAL's but where should I start and what intervals should I do? .010, .020, .030 off? .015, .030, .045 off? .020, .040, .060 off?

Powder charge: My thoughts are to start with 65gr until I work out the jump to lands and then work up from there. Any input in this area would be greatly appreciated.

 

[Sully2]

Dont know what case length is called out??....but TRIM the long ones to match the length of the short ones. De-burr th inside and outside of the case mouths

Ive never weighed an empty case in my life.......Im not after bughole accuracy

Get primer pocket tools....BOTH a brush AND a uniformer. They dont cost that much $$

Deburr flash holes. Ya need to do it once at least

Jump to lands. I insert a slug and use blue Sharpie or MarksALot to color the slug......run it in the chamber and raise and lower the bold ( NOT withdraw the bolt) and you will see a small circular mark on the slug where the rifling starts. Measure it and back off .020.

With 4831 loads are 62; 64; 66 grains...with 66 being a MAX load but with 64 grains being their most ACCURATE load!!! Ya might try 6 or so rounds at 62 grains and work up.

 

[trophyhusband]

Dont know what case length is called out??....but TRIM the long ones to match the length of the short ones. De-burr th inside and outside of the case mouths



With 4831 loads are 62; 64; 66 grains...with 66 being a MAX load but with 64 grains being their most ACCURATE load!!! Ya might try 6 or so rounds at 62 grains and work up.

Thanks for the response. The max case length is 2.850 with a "trim to" length of 2.840. Since quite a few of my cases are shorter than the trim to length, would you suggest trimming the long ones to 2.840 and let the short ones "grow" with use? How much shorter than 2.840 can I use at this stage?

Can you tell me where you found the info on the powder charge? I have a Speer manual that lists 66, 68, and 70 gr of 4831 and a Lyman manual that lists 62-69 gr with 69 being their most accurate.

 

[DPO]

Ill second Sully as a great way to get going. And have fun with it

 

[Dr. Vette]

If you have used 180 Partitions in factory ammo, and the accuracy was at least acceptable, then copy the OAL of those factory loads as a starting point. You can always fine tune from there for accuracy.

 

[Shooter00]

When developing a load, the more things are consistent, the easier a time you'll have at finding that honey load.

I'd sort out the longest cases, all being either new or once fired and trim them all to the trim to length. You can always use the shorter ones for production, they'll be accurate enough to kill. Trim, chamfer, debur, uniform all the R&D cases, making everything as uniform as you can. Measure every powder charge, trickle to desired weight. I seat the bullet half way, turn the case 180 degrees, and complete the stroke. Just what I was taught way back when.

With less variation in the components as you develop, the better results you'll have. The slight inconsistencies of the production lot won't be noticeable when you hunt, like cases that are a bit shorter, or .10gr of powder difference.

Enjoy! It's man-therapy

 

[Time Killer]

I've got a question, I'm somewhat new to this myself. I was told to weigh my brass. Ok great, but now what? Obviously I can load them separately, but should I be adjusting my charge based on this. Confused. Made no sense to me.

 

[Bart B]

Back in the 1950's when high quality match bullets were finally available, folks shooting the .300 H&H in competition at the longer ranges got best accuracy doing the following:

Handload new cases sorted to 1 grain spread in weight, no prepping of any kind needed, 69 to 70 grains of IMR4350 (2/10ths grain spread) with 180-gr. bullets or 66 to 67 grains with 200-gr. bullets, seat bullets out to just touch the lands. Sub MOA accuracy at 1000 yards was easily attained with a properly built rifle. Sometimes new cases need to be resized to uniform the neck dimensions.

Reloading fired cases, full length size fired cases in a die without an expander ball but its neck diameter about .002" smaller than a loaded round's neck, use a die that sized the case body all the way to the belt (Innovative Technologies - Reloading Equipment), set fired case shoulders back about .002", same powder and bullet data. Same accuracy as with new cases.

Regarding case prepping and powders.........

As long as neck wall thickness spread's less than .001", turning necks ain't needed.

Case length can vary .005" and it doesn't matter as far as accuracy goes.

Nothing need be done to primer pockets nor flash holes. Your choice of primer makes a bigger difference than prepping the back end of the case. Wolf/Tula large rifle primers seem to be excellent these days.

Many folks tried 4831 but it never produced quite as good of accuracy as 4350. Yes, 4831 puts bullets out a bit faster with the same peak pressure but the bullets didn't land on target as close together as what 4350 did.

 

[MudRunner2005]

To answer your question in a very legit and simplified response.....Everything is important when reloading. There are no minor details that should be left out, overlooked, or skipped. That's how people end up blowing up a gun, and hurting themselves.

 

[Shooter00]

I've got a question, I'm somewhat new to this myself. I was told to weigh my brass. Ok great, but now what? Obviously I can load them separately, but should I be adjusting my charge based on this. Confused. Made no sense to me.

From what I understand, it's a volume thing. Separating cases into equally weighing groups should keep the interior capacity relatively consistant. If I weighed out 100 cases, I'd take the largest group of the same weight (+/- a tenth of a grain or so) and use those for load development.

I guess it's assumed that the difference in case weight is a result of a difference in wall thickness. If everything is to the same spec on the outside of the case from resizing and trimming, then the interior volume would be effected by thicker or thinner walls. This can change burn times and pressures, leading to anomalies in accuracy. I've never chased that tail, not shooting BR and needing gnat's *** tight groups.

 

[Bart B]

From what I understand, it's a volume thing. Separating cases into equally weighing groups should keep the interior capacity relatively consistant. If I weighed out 100 cases, I'd take the largest group of the same weight (+/- a tenth of a grain or so) and use those for load development.

I've not seen any significant difference in accuracy of 30 caliber belted magnum cases in the 230 grain weight range varying 2 grains or 2/10ths grain. Both have shot sub MOA at 1000 yards for 15 or 20 shot test groups. That's as good as what the long range benchresters get sorting cases to exact weights.

 

[roninflag]

Trophy- you say what caliber . you do not say what rifle/scope. i like the nosler partition for hunting. the last elk i killed was with a 180 partition. they do not group as well as others ( no matter what details you do) still they are great for hunting. use WLRM , 9.5M OR CCI250 primers. weight sorting the brass may help with the vertical . 1.25 moa is plenty for elk. i have rifles that do real good ( .5-.6) but do not do as well at 400.

 

[Shooter00]

I've not seen any significant difference in accuracy of 30 caliber belted magnum cases in the 230 grain weight range varying 2 grains or 2/10ths grain. Both have shot sub MOA at 1000 yards for 15 or 20 shot test groups. That's as good as what the long range benchresters get sorting cases to exact weights.

Works for me, I've never gone to those lengths to squeeze every last bit of accuracy. Good to know it's nominal at best.

 

[trophyhusband]

B

Many folks tried 4831 but it never produced quite as good of accuracy as 4350. Yes, 4831 puts bullets out a bit faster with the same peak pressure but the bullets didn't land on target as close together as what 4350 did.

Interesting. I went with the 4831 because that's what the reloading manuals I have used. I don't know enough about the differences in powders to branch out from that right now, but once I get through this hunting season I'll do some more R & D.