I bought 4 boxes of ammo for my Ruger #1V 25-06 when I first bought the gun (this past Xmas). There were 2 boxes Remington (R-P), one box each Winchester (WW Super), and Federal (F-C). With regards to factory ammo it liked the Winchester stuff the best but I bought factory ammo mostly to have some brass to handload.

I have been working these 80 cases pretty hard over the past few months as they are the only ones I have. Most of my loads have been both consistent and accurate. Always looking to do better, I was putzing (highly technical term universally understood) around the reloading bench tonight and was wondering why some of the fired rounds have more blackening on the neck than others. They had the same bullet and same powder. I started measuring neck dimensions on spent, in-process, and loaded ammo.

All sized brass ready for loading measured 0.2545" ID, the diameter of the sizing rod on my LEE Collet Neck Die.

All fired brass measured 0.2905" OD. I don't know if that's a lot or normal or tight for a 25-06 but it's what my gun produces.

The OD of the three different makes of sized brass were (measured with my dial calipers):

WW - .284 to .2845 (29.5 to 30. mils / 2 = 14.75 to 15.0 mils thick necks)
R-P - .285 to .2855 (30.5 to 31 mils / 2 = 15.3 to 15.5 mils thick necks)
F-C - .2855 to .2865 (31.0 to 32.0 mils / 2 = 15.5 to 16 mils thick necks)

All of the like-brand brass seemed to me to be pretty consistent in wall thickness. Thin to thick over the 3 types yeilds about an 8% variance. Is that a lot? How will it impact accuracy? I haven't been segregating the brass during loading and I do notice a different feel when crimping with the LEE Factory Crimp Die.

I noticed the F-C brass had the least amount of blackening and WW brass had the most blackening. If blackening is the result of low pressure not expanding the neck to fill the chamber does all this stuff make sense?

I have fired all this brass 5 (going on 6) times. I haven't annealed any brass yet. My sizing is just neck sizing and I have no problem closing the action on the gun with the fire formed brass regardless of manufacturer. I will start keeping the brass separate during loading. I want to buy more but I don't know what the measurements are trying to tell me (if anything) about the brand I should buy.

The most common explanation for blackened cases is the load pressure being too low to keep the brass pinned to the chamber. I have no idea how hot or mild your load is, so I don't know whether this idea applies? Hand in hand with it, however, would be hardness of the case necks. Work hardened brass gets springy and is more resistant to deforming in either direction.

I am wondering, though, if you have measured the diameter of your chamber at the neck? Did the pre-resized diameters of the necks get smaller with successive loadings? If so, that would be a sign of hardening.

Nick

Most all US factory commercial ammo is already annealed. They spend lots of money to shine the cases back so they don't look "ugly".

As you shoot, you're workhardening the brass as explained above. You can reanneal easily enough with a propane torch and a bucket of water - been explained many times on the board, also.

To me, sounds like your neck chamber may be on the large size and likes the larger FC necks to more quickly seal off the chamber from the bore pressure. The W-W, being the smallest, doesn't seal off as quickly.

A reduced load on my cases is normally indicated not only by blacker necks, but shoulders and sometimes the front of the case body.

Usually don't worry overly much with blackened necks as long as the shoulders still look shiny.

The loads are near max loads using Retumbo powder. All loads are compressed. The WW brass has the greater case capacity by about 2+ grains.

There is no blackening on the case shoulders whatsoever. It stops abruptly at the base of the case neck. I'm thinking the chamber neck dimension is on the large side. Mayber I should measure the rest of the case to see how it compares to SAMMI standards. I will certainly measure new brass when I get some just to establish a baseline.

Retumbo is very slow, and with some very slow powders, a bit of discoloration of the neck is pretty much a given. They just can't expand in time to completely seal it, before a bit of gas comes back.

I wouldn't worry about it.

I anneal my cases about every 5-8 firings if I remember. I just set them in a cake pan with about 3/4-1 inch of water and use a propane torch on the necks/shoulders til they get red. Tip them over and your done.

One thing I do is try to stick with one case mfg. when I buy cases I usually get at least a hundred and if I'm in the chips 500. This will last a long time.

Like Mike said when you use slow powders like retumbo blackening is almost a given. I just chuck them in the tumbler after depriming so it goes away. I also like to deprime with a universal depriming tool so I'm not sticking those dirty cases in my resizing die.

Of all the rifles I've had over the past 50 years I've never owned a 25-06 or a 270. My brother-in-law had a Ruger 77 25-06 he used for coyotes when they still had the safety on the tang. Very accurate and very deadly out as far as he could shoot it. worked great on deer too.

I have a #1B Ruger in 243 that I really like. It was built in 1979 and has a good trigger and one of the prettiest stocks I've seen on a #1.

Good luck with your #1, I really enjoy mine.