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BudT
01-22-2014, 06:03
For years I have always wanted to know "why" after 3-5 shots with .300 Win. Mag brass they all get sticky to chamber even after full length resizing. Yes the cases are trimmed and yes the full length dies are set correct. This is in bolt guns, no the loads are not "hot" or even pushing the edge of hot. TIA

BudT

Matt Anthony
01-23-2014, 04:00
Budt:
I had the same problem and corrected it by not shooting 3 to five shots at one time. In hunting, one has maybe one shot, maybe 2 in the narrow time span an animal stays in one place. So, limit your groups to 2 shots and then let the rifle cool. Take a 22LR or a another gun when shooting the 300 to take up the cool down. Besides, why punish yourself any further as the old rule of 5 shot groups is rediculous and waste full!
I went through polishing the chamber on both of my 7MM Win. Mag and the 300 and found no difference, other than ejection was easier. Regardless, looking at my loadings of yesteryear, 72 grains of 4350 with a 180 gr. bullet is still hot! It's a hot cartridge from the get-go!
As I have stated in the past, with rotator cuff problems all of my larger rifles had to be sold so I don't have to worry about it anymore. I stick with the ole 222 Rem. and 22-250's and enjoy pill shooting with my benchrest 22's at 100 yards.
Matt

BudT
01-23-2014, 06:50
Thanks Matt, as a rule I don't shoot 5 shot groups at one run. If I do put 5 in there is a cool down time in between each shot the exception would be a rim fire. I'm pretty much a 3 shot group shooter and those almost always have a little bit of time between shots unless it's shooting at game then "it's on until the end". My .300 is a exceptionally accurate rifle and to shoot that good it has to be near the top end, but not at it. My standard all round use hunting load is 150 grain Barns Tipped TSX over 76 grains of IMR 4831 a Remington case primed with a CCI250, it's a do everything load. The cases will fall out on their own with no primer signs of to much pressure, rounded edges as like new. Barns book #4, I have shot several 3 shot back to back groups you could cover with a dime at 100 yards, good enough for me and my kind of use. If I understand you correctly your saying that it is the heat expansion that allows the case to enlarge.

I'm not bothered by recoil but I don't have a physical problem on that side, yet. I am still thinking of having the sako extractor put in to replace the original Remington type. At any rate thanks again for you input it helps.

Regards
BudT

PhillipM
01-23-2014, 09:16
I'm not saying this die will solve your problem, but it might. It's on my long list of goodies to buy one day.

http://www.larrywillis.com/

http://www.larrywillis.com/diesmall.jpg

"A Collet for Belted Magnum Cases

Belts on the belted magnum case were put there for headspace control and not for strength, as is sometimes claimed. Once the case has been fired, the life of the case and perhaps accuracy, can be improved by headspacing off the shoulder rather than the belt. This is easily done by backing out the sizing die so that it doesn't set back the shoulder any more than just enough to insure that the case will chamber freely in the gun.

Because of the taper in ordinary resizing dies, the back end of the case (at the pressure ring), is usually left slightly larger in diameter than desired. Innovative Technologies has come up with a clever solution: a collet-type resizing die that sizes the body of the case right up to the belt.

In use, the die body is screwed into the press from the bottom. A fired case is dropped into the top of the die. If it drops in freely to the belt, there's no reason for any further sizing. If it fails to drop in freely, the case is removed from the die body and the collet is slipped over the case until it bottoms on the belt. The case and collet are then pressed up into the die body in the usual way. The collet is squeezed against the case by the die body and resizes it. When the case is removed from the die body the collet comes out with the case and is then slipped off.

Neck sizing, and any required reforming of the shoulder, is then completed using the regular dies for the caliber. All the basic belted magnum cases can be sized using the same collet. This collet die works very well and is a very useful accessory to the reloader of the belted magnum cases.

- Craig Boddington"

"Belted magnum cartridges have been around for over 50 years, and most shooters that reload them are familiar with the case bulge problem that occurs "just above" the belt. This usually happens after just 2 or 3 firings - wasting perfectly good cases. Many shooters have discovered this problem when they find their handloads begin to stick in their chamber, or when they no longer chamber at all.

Unlike non-belted cases, the belt prevents conventional full length dies from traveling far enough down the case. This limits the amount of resizing, and brass is plowed rearward. The brass builds up just above the belt at each reloading, and cases expand. Neck sizing dies don't bump the shoulder back or resize the tapered case wall. The best solution is to full length resize accurately, and use this collet die to reduce case width."