Figuring out a new Method

[Sweetroels]

I've always did the standard easy case prep. Cleaned brass, X full length resize, cleaned pockets, trimmed, primed, loaded powder and seated bullets. My groups at 100 are ½ inch once I find the correct powder and bullet on all my guns (6). I use Lapua and ADG brass, never tracked how many times brass was shot, either too lazy or didn't know any better.

Now I am tracking all brass, and want to just bump the shoulders after 1st​ use and maybe use an expanding mandrel sizing die. I have RCBS Neck dies, is this what I use for bumping the shoulders? Clean, bump shoulders, expand die, clean pockets, trim, prime, load powder seat bullet. Is this a decent method? Someday I will get an annealer but not yet

I am primarily a hunter but love the range and reloading which I've done for years. I want more consistent grouping with one of my guns, the 300 RUM shooting beyond 400. I have the 300 in a Christensen Traverse topped with a Swaro Z8 and would like to get proficient out to 800 yards. I understand it takes more than good brass prep to shoot well out that distance but just want to get advice on the brass part for now. Sorry for such a neophyte question for most here. Thanks for any advice

 

[jamie eaton]

Following .

 

[VinceMule]

I worked up an incredible load for mine in one afternoon with 180g Accubonds, fed 215s, and IMR 7828. The accuracy node where all the bullets were knawing out a hole was at 3300 fps and over the book max load.

I bedded the rifle, adjusted the trigger, and added a muzzle break before ever firing a single shot.

600 yard groups were excellent, plenty good enough for varmints, must less deer/elk.

 

[ShtrRdy]

The people who compete in shooting sports that require a high degree of precision and sometimes accuracy always full length resize the brass.

 

[Sweetroels]

The people who compete in shooting sports that require a high degree of precision and sometimes accuracy always full length resize the brass.

Thanks ShtrRdy. I see so many opinions. Why do a lot of folks say to fireform brass so it fits the chamber then work up your loads? Are we starting one of those religious fights?

 

[VinceMule]

In quality barrels, with custom chambers, I have had great luck with new Quality brass, such as Lapua and AGD, 3/8" groups and smaller. No doubt that loads may have to be altered a tiny bit later on due to several reasons, but the load tweak is small. I full-length size on every firing or, at a minimum, a partial full-length size, depending on the caliber. If the bolt closes easily on one round, then with some resistance on another round, there can be flyers associated with this inconsistency.

One reason that you see so many opinions on this issue is the difference between new brass and chamber dimensions. Some chambers are very close to chamber dimensions, while others are wildly different. Also, the Rockwell hardness of brass varies by brand and can differ by as much as 6% within the same lot# of the same brand. Another issue that crops up it's ugly head is that accuracy at 100 yards can be radically different than accuracy at 600 yards, where little things can make a big difference.

Trial and error with an open mind is key to success. Don't be scared to fail, fail till you can.

The vast majority of reloaders are at some phase of learning to tune a load, and once you learn to tune a barrel, it can be amazing how factory rifles can shoot, much less customs.

 

[Hobo335]

Thanks ShtrRdy. I see so many opinions. Why do a lot of folks say to fireform brass so it fits the chamber then work up your loads? Are we starting one of those religious fights?

Amen !!!

 

[Hand Skills]

Here is a great article on how to figure out shoulder bump.

Maintaining Consistency In Your Brass

Maintaining Consistency In Your Brass By Jim See My last article on brass prep centered on preparing new brass for loading. This article will cover maintaining that brass for long life and the processes I use in my brass loading prep. What I am...

www.longrangehunting.com

A comparator is nice for this;

Lock-N-Load® Headspace Comparator & Anvil Base Kit - Hornady Manufacturing, Inc

Lock-N-Load® Headspace Comparator & Anvil Base Kit Lock-N-Load® Headspace Comparator The Lock-N-Load® Headspace Comparator extends brass life, improves accuracy, and enhances safety. The gauge measures...

www.hornady.com

I'm cheap so i just use the .375 bushing from the bullet comparator set when I want to measure shoulder bump on brass.

https://www.hornady.com/reloading/precision-measuring/precision-tools-and-gauges/lock-n-load-bullet-comparator#!/

Keeping it simple, masking tape and a Full Lenth Sizing die is all you really need to get a small yet precise bump though.

 

[ShtrRdy]

Thanks ShtrRdy. I see so many opinions. Why do a lot of folks say to fireform brass so it fits the chamber then work up your loads? Are we starting one of those religious fights?

The reason for fire forming brass and then doing a full length resize with a small amount of shoulder bump, (push back), is to get all the pieces of brass the same size. In other words it gets all the pieces of brass consistent to each other. The internal volume of the case will be close to the other cases internal volume and the amount of energy needed to expand the case to the chamber walls will be more close to each other.

 

[Bob Wright]

Hit the search button and look for full length sizing. It's been covered extensively here.

 

[Jamie]

If your die is a true neck sizing die then it will not, should not bump the shoulder. It is neck only. You may be able crank it down to get some shoulder movement but it could also bulge the shoulder because of lack of case support.


I tumble, anneal, lube, size with RCBS Full length Bushing die, expander mandrel, tumble, prime, load powder with Autotrickler 4, Forster Micrometer seating die to seat bullet. Moving to my XL750 to cut down on shoulder wear, mine not the cases.

 

[VinceMule]

Not many know it, but the standard Forster Neck sizing dies are shoulder bump dies. My last Rem 25/06, I shot the barrel out and never full length sized the Winchester brass, just bumped the shoulder on every firing, 85-87g bullets at 3600 with IMR 4350, uncanny accuracy.

 

[nksmfamjp]

FL Size or bump because full 65ksi loads stretch things a bit and you want your handloads to seat and center naturally in the chamber.

I'm actually surprised anybody is neck sizing still. I don't see a case for when that is a better choice than FL Sizing with a slight bump.

I still wonder what the case ever was for neck sizing except maybe dies and chambers were more different with more machining variation in the past??

 

[VinceMule]

Neck sizing all started in the 50 with cases that had a LOT of body taper and case stretch on every firing, like the 220 Swift and 22 High Power. Neck sizing does not work the brass as much leads to less case stretch, ie. less case trimming.

Recently, it has been found that at least a partial full-length sizing helps accuracy with consistent case dimensions.

Fads come and go; you could not believe the crap that was popular in the late 60s- early 80s in benchrest shooting.