I own 2 .300 WSM -- a Browning A-bolt II and a new Kimber Custom Classic. The problem is with the Kimber. Rounds sized for the Browning will not chamber in the Kimber. OK, the Browning chamber is a little bigger. BUT, cases FULL LENGTH SIZED for the Kimber, even new brass, are tight or refuse to chamber. I am using early RCBS .300 WSM dies. Do I have a "sloppy" set of RCBS dies, not setting the shoulder back far enough, or a Kimber that is chambered too tight? I should also mention that factory Winchester rounds chamber fine in the Kimber (maybe a little snug, but I can close the bolt), so I'm thinking the dies are just a little long. Someone in Snowcat's thread recommended filing/stoning the top of the shellholder to set the shoulder back a bit more. Is this the answer?

TIA....

MKane160

MKane, I am no expert but I have a Tikka T3 Lite in 300WSM that has the same problem as you are having. I used my belt grinder on the bottom of the F/L sizing die and ground it down a few thousandths so that I could knock the shoulder back a little more. This fixed my problem. I think a lot of rifles chambered in this caliber have very tight chambers. I know another guy that can't seat his bullets out to Saami specs bacause they will be into the rifling and that is with 165 grain Hornady SST's.

There sure seems to be alot of this problem with this caliber. Possibly related to turning out alot of guns in a short time span (and dies too) where new reamers and worn out reamers are causing slight tolerance problems. (is there such a thing as a "slight" tolerance problem?????)

Shoulda bought an "SAUM" in the first place!!! Better design but piss poor marketing!!! GHD

old reamer maybe.

quote:

Originally posted by MKane160:
I own 2 .300 WSM -- a Browning A-bolt II and a new Kimber Custom Classic. The problem is with the Kimber. Rounds sized for the Browning will not chamber in the Kimber. OK, the Browning chamber is a little bigger. BUT, cases FULL LENGTH SIZED for the Kimber, even new brass, are tight or refuse to chamber. I am using early RCBS .300 WSM dies. Do I have a "sloppy" set of RCBS dies, not setting the shoulder back far enough, or a Kimber that is chambered too tight? I should also mention that factory Winchester rounds chamber fine in the Kimber (maybe a little snug, but I can close the bolt), so I'm thinking the dies are just a little long. Someone in Snowcat's thread recommended filing/stoning the top of the shellholder to set the shoulder back a bit more. Is this the answer?

TIA....

MKane160

Well, if you grind down the dies so the cases you are resizing fit the Kimber, then you are going to have headspace problems with the Browning.

I would do a casting of the Kimber chamber, and then compare it to SAAMI specs. If they don't match...raise hell with Kimber!

quote:

Well, if you grind down the dies so the cases you are resizing fit the Kimber, then you are going to have headspace problems with the Browning

I stand to be corrected
but if he turns the die back to as only resize the neck for the Browning would he not be okay?
I would not be to much of a hassle.
but if th chamber is short he should raise hell with Kimber.

I have three Kimbers and they all have tight headspace. Some virgin brass causes the bolt to close with slight resistance. I had to take .010" off my RCBS 22-250 die to get the proper sizing.

An option is to take the required amount off the top of the shell holder. Seeing the tight headspace, in my mind is a good thing, as long as it's not tighter than the spec'd minimum. I think most off the shelf dies won't quite get it for the bare minimum headspace, for some reason. I would also suggest you get another sizing die for the other gun, and dedicate it and brass to it only. I always keep brass seperated for each gun.

I took the metal off the shell holder. Cheaper than the die. Plus if I ever sold it the die would be "factory".

I had the same issue. My rifle required a shortened shell holder. My buddies required the die not to touch even a factory holder. I set the die up for mine and then used a shim to raise the die for his. Or you could get two shell holders alter one and leave the other factory.

Since you own both then you can do the same. Keep brass separate. Maybe use different brands for each rifle.

Check out Redding...they have competition shellholder sets that vary headspace by 0.02 steps.

All good advice, but I'll throw this in before you run away and grind your die, get competition shellholders or whatever.

If you are ABSOLUTELY SURE the problem lies in insufficient set-back of the shoulder, then you can start thinking of modifying your die, shellholder or whatever. (More about this later, though). The only way I know of measuring this (with not perfect but reasonable accuracy), is using some sort of a headspace gauge. You have to measure both fired (in both chambers) and FL sized cases, and make sure you measure all cases in one go. That way you have the best chance of avoiding setup errors creeping into your measurement series. I personally use a Stoney Point Head Space Gauge for this, but there are other options. Only when you have a pretty good idea of the measured head-shoulder measurement is on both fired and sized cases, can you sensibly say whether your problem is insufficient shoulder set-back or not.

Be aware, that there is a very sloppy relationship between the different reamers used to cut chambers (as you experienced), reamers get worn, and then there are the dimensions used to manufacture the dies after. It is quite possible, that you can't chamber FL sized cases in "gun B" because of some other dimension, case diameter in front of web, say. So, you should also maesure your cases (fired and FL) at least behind the shoulder and just in front of the web. If this happens to be your problem, and you keep reducing your head-shoulder dimension, you are creating a potentially dangerous situation.

Now, even if you find that your problem is insufficient set-back of the shoulder, and you MAY be able to fix this by modifying your die, say. I personally would not go that route. Rather, I would get a set of dies for each rifle. That way, you can (presuambly) set up the die to bump your shoulder fired in THIS rifle an EXACT amount (.001 - .002") every time you size a case from that rifle. Keep the brass separate from the two rifles. IMHO, this is the better setup, at the cost of keping the brass separate and buying an extra set of dies. What you win: a much better setup, you don't have to fiddle with your dies (FL and seating!) every time you want to switch from loading for rifle A to rifle B. Living in the States, brass and dies are pretty inexpensive.

Besides, what if you manage to set back the shoulder far enough to fit rifle B, what about the head-shoulder dimension of this brass if you want to fire it in rifle A... Bad vibes there! (as Steve also pointed out above)

All in all: do not assume what the problem might be, and act in a way that could create a potentially hazardous situation (excessive headspace)! Rather establish what the problem is by measurements, and act on the basis of that. And do consider getting a die set for each rifle.

- mike

Grind down a shell holder for the Kimber. If the Kimber shoots and functions well from that die/shell holder call it good.

If the Kimber shows some other problems consider getting them to check the headspace too. I mention this as you say that unfired new brass requires some effort. Try a second brand of brass before going that far.

Remove the firing pin from the Kimber when testing for bolt closing effort as it eliminates a variable. Just put the safety on half postition, remove the bolt and turn out the firing pin from the bolt.

Look for a shiny spot on the tight brass. That will tell you much about where the problem lies.

My early production M70 300WSM requires the die to be so low as to have a hard cam-over in order to set the shoulder back enough to qualify as partial full length sizing! True FL sizing is not really possible in my setup. You might have a similar sitiation, just a bit worse.

I would grind the die myself (if you must grind anything), as I am always worried about thinning the lip on a shellholder enough to weaken it. Dies really aren't all that expensive either.

Hello the campfire:
I don't mean to throw gas into the fire, but in my uneducated opinion, I would have both of the chambers cast and and checked. I suspect a short headspace problem in the Kimber, and it should be fixed IN THE RIFLE. It is a simple fix to have the chamber reamed a little if it is off. Kimber should do it for you for free.
The other thought I had is, have you measured the over all length of your brass? Too long brass will cause hard chambering. I would compare the empties with the factory loaded cartridge to see if the Win. are not a little less that specs to allow for some strech.It is your rifle and your dies so you can do what you want. I prefer to have my equipment uniform so that I don't have to worry about two sets of dies, two batches of cartridges, grabing the wrong shell if I need it in a hurry or on one of those brain fart days at the rage having the wrong shells for the rifle I have. It happens. I once drove 30 miles to sight in a rifle and left the bolt on the work benck at ome. Don't uild your setup around a mistake.
Good Luck
Judge Sharpe

I have the same situation with my Rem 700 and my NULA both in 30-06. Brass fired in the Remy could not be sized to fit the NULA despite full length resizing. I tried this initially and ended up breaking the bolt handle trying to tap it open. The chamber in the NULA is minimum specs according to M. Forbes and I would assume the Remy is to maximum specs. My guess is that the area behind the line at the base of the brass after resizing doesn't get resized to fit.
Malcolm felt that the RCBS dies were on the loose side and sent me some Redding dies which have worked great.

I now keep my brass separated and use the RCBS dies for the Remy and the Redding dies for the NULA so I don't have to adjust them between rifles.

Thanks for all the replies, fellas. I think I need to check the fired, factory brass for size, see if it differs from reloaded fired brass. I think the stoning the shellholder method is a place to start, although if I KNEW for a fact that the Redding dies would be tighter, I'd just go buy a set of those dies. BTW, even though the Browning is chambered "sloppy" compared to this particular Kimber, it feeds and extracts slick as a whistle. And it's the most accurate factory gun I've ever owned.

MKane160

quote:

Originally posted by MKane160:
Thanks for all the replies, fellas. I think I need to check the fired, factory brass for size, see if it differs from reloaded fired brass. I think the stoning the shellholder method is a place to start, although if I KNEW for a fact that the Redding dies would be tighter, I'd just go buy a set of those dies. BTW, even though the Browning is chambered "sloppy" compared to this particular Kimber, it feeds and extracts slick as a whistle. And it's the most accurate factory gun I've ever owned.

MKane160

Redding dies do not have a vent hole. The Redding dies that I have for the 270 WSM and 7mm WSM dent the bodies of the FL sized brass. I have had to buy new RCBS dies to stop the denting.