I just picked up my 300 WinMag from a local gunsmith, who replaced a bad bolt (Mauser 98 action). He had to recut the chamber and lugs. When I tried to find the distance to the lands for my first handloading, I noticed that the leade was very long. In fact, with 180gr Hornady Interlocks barely seated into the case neck, closing the bolt only pushed the bullet in another .010. There is .040 between the case mouth and the cannelure. That seems like way too much leade to me. What should it be?

I once loaded for a Winchester M-70 in that caliber. The lead was as you describe. I bet the SAAMI spec. chamber has freebore.

Most chambering reamers have the throating built into the reamer. The distance to the lands is not a variable in that case. Unless you specified a distance to lands you're going to have to live with it as is.

Now...is this ok?...Yup...the issue of loading close to the lands is way over worked. It's a small thing in the overall scope of things.

Take the gun to the range and shoot it. See how it groups and try some different bullets and powders. It'll be just fine.

Of all my reamers only one has a throater not built on the reamer....and that's for the .375 H&H which I throat with a separate tool.

As a rule most chamber reamers come with one caliber length of throat. Weatherby rifles come with about 5/8 ths of an inch of throat and they offer a guaranty of 1 ½ inch of accuracy at 100 yards with factory Weatherby loads. They do seam to be able to back up these claims. They use the long throats to get the velocities that they advertise. Most of the Weatherbys that I have played with, and that would number in the hundreds can be improved dramatically by simply trying factory loads from other makers like Federal or Remington. These rounds come no where close to touching the lands and grooves but they still can produce dime sized groups at times. Hand loads obviously can improve things even more. The point is and don’t get me wrong here! Throat length has little bearing on hunting accuracy. Yes to the varmint shooter or bench rest shooter it is important but in a hunting rifle it makes little difference in most cases. Possibly 1/8 th to 1/4 inch at 100 yards or less. Deer tend to be pretty big. There is a flip side to the long throat. With good hand loads that long throat could give you 40 to 60 FPS more velocity than what is normally possible with the 300 Winchester. Providing you have a 25 or 26 inch barrel! Rod Henrickson

I was getting ready to work up loads for this rifle when I noticed how long the leade was. I probably wouldn't have given it much thought except that the lugs aren't bearing evenly, either. I'm wondering about the whole job now. Just how much leade should there be on the 300WM?

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He had to recut the chamber and lugs.

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except that the lugs aren't bearing evenly, eithe

This is screwy....please explain why the gun needed the chamber recut and the lugs modified.....was this because of "setback"?

I personally hate it when that happens. I don't believe it is possible to actually measure the freebore on the reamer, but if the smith does not not actually KNOW what freebore his reamer will provide, then it is time specify your own reamer.

I had this happen to me with a smith of good reputation (in the US), and I ended up with a .270 Krieger barrel with a leade much longer than I had specified (I supplied dummy rounds). In effect, that was a Krieger barrel (and costs for chambering and finish) down the drain... Since then, I have specified my own reamers, or tried to make darn sure that the smith knows how his reamer is set up.

Now, it is possible the long freebore won't affect your accuracy. Only testing will settle that issue. But in general, a long freebore is not considered advantageous for accuracy.

- mike

vapodog,
He replaced the bolt, and the fit was different enough that it was necessary to recut the lugs and lug recesses to match up properly. This changed the headspace enough that he needed to recut the chamber. This is what he told me. I don't understand why the lugs aren't bearing evenly if he recut the lugs and recesses. They really need to be lapped.