Neck Turning, Flash Hole ?'s

[Buck88]

I started reloading about a year and a half ago to save money on .45ACP and .40 S&W ammo. Since then however I've gotten into rifle reloading... and it's a whole new ball game!

I'm reloading for a Remington Sendero in .300WM, and a Kimber 8400 Sanora in .300WM. I have yet to produce any quality reloads and decided to do everything I can to get max accuracy out of these rifles. I FL sized the cases, trimmed to 2.620, and am thinking of neck turning them and uniforming the flash holes.

My question is how much to turn off the necks, and how to uniform the flash holes? I was playing around with it last night and found that if I turn them to .014, material is taken off of about 85% of the neck. But how thin can I go before they won't retain enough neck tension to hold a bullet?

Thanks guys, oh and if you have any other techniques let me know.

[Scorch]

First off, I usually tell people to work up a load that gives pretty good accuracy before they start turning necks and so on. Weighing and grouping cases, turning necks, deburring and uniforming flash holes are all fine-tuning things, and do very little to help until you have a good group to begin with.

I true the necks on my 22-250 until I get about 2/3 of the neck cleaned up, typical neck thickness in my case is about .013". You will gain very little by neck turning because the chambers in factory rifles are typically very loose, so neck turning may actually shorten your brass life significantly.

Also, just neck size, don't full length size, if you can get away with it. This will allow the brass to keep the fit of your chamber and keep the neck centered on the bore.

[Big Ugly Tall Texan]

Every rifle chamber is different.

When you fire a round through YOUR rifle, the brass takes the dimensions of that chamber. If you neck size only, so the brass will hold the bullet, you keep those dimensions so there is less room for the brass to expand and less shot to shot variability.

There are a few tricks to improve accuracy, but, as has been said, you need to get to a starting point. You need to get some sort of acceptable accuracy and work from there.

Uniformity is important for maximum accuracy - that's why it helps to weigh brass to make sure they are as close to being the same as you can get them.

Another trick that I use it to select a powder that achieve the results you want but almost completely fills the case. I use ball powder a lot.

When the case is filled, there is less air in it and therefore less room for the powder to shift and better shot to shot accuracy.

Make sure all the primers are from the same manufacturer and if possible from the same lot... again it removes one more variable.

I used all of those tricks and worked up a load for my Syrian (Yugo) 8mm Mauser that allowed me to put five shots in one hole from the bench at 100 yards. Having the scope dialed to 24 power for my old eyes also helped some.

More:

Each rifle is individual. Different rifles work better with different bullet weights and different powders. I don't understand why that is true, I just know from experience that it's true.

When I am working up a new load, I take a Lee handpress, about 50 or 100 rezied and primed cases, three or four different bullet weights - Boat-tailed HP if possible, and three or four different types of powder to the range and have a ball experimenting.

To me, that is the main attraction of handloading for a rifle - not trying to save money, but trying to match a particular load to a particular rifle and tweaking out every fraction of an inch of accuracy.

Handloading for a handgun, I'm just trying to produce as much ammo as I can to get in as much trigger time as I can for the dollar.

And I don't worry about turning or trimming brass until the third reload.

[Tuzo]

My 5-shot groups significantly decreased in diameter (3/4" at 100 yds) after I began neck sizing .223. Other rifle calibers (.30-06 and .243) followed suit after neck sizing. This works only for bolt action rifles. In addition to neck sizing I uniform the flash hole, trim to length, segregate cases by head stamp, throw and weigh powder with an RCBS Chargemaster, and use Sierra match HPBT bullets. So far I have avoided neck turning because I want my brass to last as long as possible. Annealing has been considered but I still must weigh its advantage in relation to the effort. Ten reloads per casing and counting with, for me at least, more than acceptable accuracy.

[Big Ugly Tall Texan]

I only say that because I went through the same thing and had two case head separations on a 7X57.

The blowback was rather annoying and while I was able to remove the first separated case myself, I had to pay a gunsmith for the second.

I then pulled the bullets from the rest of that bunch of handloads, stored the powder and threw the brass away. That was about 30 years ago and since then I never reload a case more than six times. Just a number I pulled out of the air when I decided to set a limit.

[Buck88]

Thanks guys, you all made some interesting and meaningful points. I ordered a neck sizing die about a week ago from midway. I want to prolong case life and know that neck size only is a good attempt at that in addition to a possible increase in accuracy. Also, I have read some disputing arguments that the .300WM headspaces on the belt. I still don't know where it headspaces, so the neck size die will ensure that it HS's on the shoulder.

I'll agree that I should get a baseline before fine tuning though. The reason I got into reloading for rifle is because I wanted to tailor rounds for particular circumstances and also attain the best possible accuracy, but I'm getting ahead of myself a bit I think. Also considering that I took a step up from a 7x57 to a .300WM, my groups aren't going to be looking good for awhile anyhow.

[ForneyRider]

Progression on my brass prep.

1) neck-size, trim, chamfer neck, debur outside of neck. First with Lee, then with RCBS and Redding.

2) flash-hole debur with Redding tool($20). RCBS, Hart and other make these.

3) primer pocket uniform with Redding tool($20). RCBS, Hart and other make these.

I haven't noticed any noticable improvement in the last 2 steps.

Adjusting neck tension by only sizing part of the neck is a handloader trick to avoid shaving necks and using 180$ bushing dies. You can get a runout gauge to check concentricity of the mouth of the brass and pick the best group of brass.

Experimenting with different OAL and primers may make some improvements after you get a good powder charge.

Nosler brass is excellent and available in 300 WM. Nosler is match prepped and weight sorted. You can save a lot of time to be used experimenting with OAL and powder charge, etc.

The number one thing I read over and over, is the bullet is the biggest difference in accuracy.

The coppers next to me at the range the other day were shooting 208 A-Max and R25 with a supposed 3000fps in their Rem 700 police in 300 WM. Their chrony, as well as mine, was acting up in the noon day sun. Their rifle had a brake and a big scope. Their groups at 100yards were fist sized. Mine were 1.25 to 1.5 inch. The one guy said they were testing 1/10gr increments in powder. I've gotten better groups with hunting bullets but these were my first 168gr SMK experiments with R25. If I don't get better with my next batch, I will switch to R22 or IMR 4350.

[Major Dave (retired)]

You mentioned weighing brass to increase uniformity.

How close to the same weight should they be?

Specifically, I weighed some RP brass in 7X57 Mauser, with these results:

1. 185.2 gr, 25 pieces
2. 185.5 gr, 10 pieces
3. 186.0 gr, 21 pieces
4. 186.7 gr, 24 pieces
5. 187.5 gr, 10 pieces
6. 188.0 and higher, 12 pieces

So, should I group them within 0.3 grains, (groups 1&2) 0.8 grains,(groups 1, 2, and 3), or some other grouping?

I am intending to start from scratch to work up a load of Barnes 140 gr Triple Shock X bullets for elk hunting. I expect to get 2900 fps MV, using IMR 4350.

Thanks for your advice.

[flashhole]

Forney Rider wrote

"2) flash-hole debur with Redding tool($20). RCBS, Hart and other make these.

3) primer pocket uniform with Redding tool($20). RCBS, Hart and other make these.

I haven't noticed any noticable improvement in the last 2 steps."

I agree, I have not seen where these steps make a difference in accuracy in handgun loads or large-case-capacity rifle loads (with the exception of my 25-06). I have seen a significant difference/accuracy improvement doing these added work steps for small caliber, small-case-capacity rifle loads and I will throw primer selection in the mix too as one of those things you can control that makes a noticible difference in accuracy.

I have been fortunate in that I can/do resize cases from larger ammo, 30-06 ==> 25-06 and 223 ==> 221 Fireball. In both instances I end up with excessively thick necks that must be neck trimmed. I trim for a tight fit to my guns chamer and that is good for accuracy.