I am new at this so bare with me. I was using Sinclair tool last evening and two separte 30-06's measure 3.30 and 3.40 to the lands. The first being a pre-64 std 24" win and the second a pre garcia sako deluxe. I am just getting used to these measurements and realize we are talking like a 1/10 of an inch. Question is is this pretty common or really not normal? How much difference in the same caliber on a Factory rifle should be a concern?

Chambers come in all sizes, in particular factory chambers. I'm not the least surprised to see a difference in freebore of .1" betweeen two factory guns in the same caliber.

When you start looking closer, you may see all sorts of dimensional differences - some of which could potentially be a lot more "worrisome" than the freebore. Case in point, this weekend I wanted to set up my FL sizing die for a .30-06. I wanted to use nickled brass in anticipation of an African trip next year. I happened to run into some Rem nickled cases fired in a different .30-06, so, presto, here was my case material for load devlopment and die setup. Well, it turned out that the chamber (head-shoulder) length on the target .30-06 was a good .01" longer than on the chamber in which the cases had been fired. Had I set up my die to simply push back the shoulder .001-.002" based on the fired brass, I could potentially have created a headspace problem in the new chamber.

Chambers come in all sizes and all shapes - as do dies. It should teach us a couple of things: 1) (FL) dies and brass should kept separate for each chamber, and 2) it is definitely not evident that ammo set up to be safe and shoot well in one chamber will display the same attributes in a different chamber. The fact that two rifles come in nominally the same caliber really means comparatively little during the reloading process.

- mike

And don't you reckon this causes headaches for factory ammo loaders?!

Mike as I understand what you have said in keeping FL die and brass separate for each "chamber" would this not be as important if one is using cases that are fire formed in each rifle to be reloaded for. My plan, as I have been saving fire formed brass from about twelve rifles for several years, is to reload this brass for each rifle for about three or four reloads or if they get hard to chamber and then FL size. Question, are you suggesting one needs a separate FL die for each rifle one reloads for?

quote:

Originally posted by muygrande:
Question, are you suggesting one needs a separate FL die for each rifle one reloads for?

That is what I do. It costs a bit more and leads to more dies on the shelves, but it allows you to adjust a die for one particular chamber. In fact, I also keep seating dies separate for each rifle/chamber - simply to avoid having to adjust the seating stem all the time. The only dies I (sometimes) share between rifles are NS dies.

quote:

Originally posted by muygrande:
Mike as I understand what you have said in keeping FL die and brass separate for each "chamber" would this not be as important if one is using cases that are fire formed in each rifle to be reloaded for. My plan, as I have been saving fire formed brass from about twelve rifles for several years, is to reload this brass for each rifle for about three or four reloads or if they get hard to chamber and then FL size.

If at all possible, I "assign" brass to a particular gun from the outset (exceptions confirm the rule). That brass stays with that gun until the gun goes or the brass is bust. If I can NS the brass and still have it chamber well and produce good accuracy results, fine, in that case I may use a NS die. If not I'll use a FL die set up for this particular rifle/brass. There is no guarantee brass sized such will chamber in another rifle of like caliber.

Attention: a lot of NS dies are problematic in terms of producing run-out. They simply don't support the brass very well during the sizing operation. Good NS dies include the (cheap) Lee Collet die and the (expensive) Redding bushing neck dies.

- mike

Well I opted out of the Redding bushing type and went with their standard FL/NS die. Guess I will be keeping an eye out for the runout. I just couldn't wrap my arms around the 100's of bushing sizes to choose among.

quote:

Originally posted by muygrande:
I just couldn't wrap my arms around the 100's of bushing sizes to choose among.

I agree. That is where the Lee Collet dies fit in. Try investing in one (about $20 for .30-06) and I'm pretty sure you won't be disappointed.

You may think it is wasteful to buy several die sets for a single gun, and indeed you would be right. Take comfort in the fact that I'm on the third set of dies for some rifles until I ended up with the dies that did what I wanted them to do.

Next time you buy dies, consider the Forsters an option. Not only are they good dies (in particular the seaters), but Forster will modify the FL dies for you to be used without the expander. This is a great FL set-up. Cost for the modification: $10 plus shipping - one of the true bargains in the reloading World today.

- mike

I will try the Lee's as I have a few calibers still to set up for although they are the mag calibers in 300/375 H&H and 300 Wby. I left them behind just so I could get up the learning curve on all the '06 based calibers before bothering with the belts. Thanks for sharing your experiences.

quote:

You may think it is wasteful to buy several die sets for a single gun, and indeed you would be right.

It is not always wasteful. By using multiple brands of die sets and rifles in the same caliber (sometimes as many as a half dozen of each) I have learned quite a bit.
1. Rifle chambers and throats vary a lot even between the same make and model.
2. Dies sets vary a lot, sometimes even between different sets of the same die brand. Other times different die brand will have almost exactly the same dimensions.
3. A really bad chamber and barrel are difficult to do anything with, but you can often make decent ammo with crummy dies though I don't recommend trying.
4. It pays to set the headspace up exactly right for your loads. Ammo is consistently more accurate when the headspace is uniformly set to about .001 clearance vs what ever you think you get when set up without measuring the headspace.

Couldn't agree more!
- mike