300wm sizing ?

jetmd

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Minuteman
Jan 17, 2010
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Smithville, MO
Disclosure: I have been reloading since 1985, but this will be my first learning exercise in reloading a belted magnum cartridge.

1) How many of you use the Innovative Tech Belted Magnum Collet Resizing Die?
2) If you use it, is this step required ever time or only required after (X) number of firings from your chamber?
3) Are you using a shoulder bump/NS die then just following up with the collet to ensure ease of chambering? Or a FL die?
4) Tips you would like to bestow upon me in regards to reloading the 300wm ?

Further info, my chamber is a A191 cut with a JGS Reamer. Brass is Black Hills Match, fired 1x from my 300wm.
Use will be recreational target shooting only. No hunting, No comp's. Just Fun thumping steel.

Thank you in advance for your response!
 
You are taking about the Larry Willis die? I think Rob01 whom is a moderator here uses it from the best of my memory. Personally, I've never used it, and had not seen the need in my 300wm brass after 4-5 firings. I don't think it is essential, but probably something good to have if you are shooting a ton of belts. All I did was F/L size each time.
 
I use RUAG T brass in the 300 WM and full length dies. Neck tension is set using lee collet die. I do have the Larry Willis die but aftet 5-7 firings on cases I have yet to have a need to use it. With thin walled weaker brass, perhaps need might become apparent? also, I have thus far not seen a need to re-anneal the cases.
Use quality brass and you will have few problems with what is an easy calibre to load for. Note well: case capacity varies substatially between headstamps, as does brass quality.
 
I have been using the redding comp 3 die set for 18 years now, I use the body die to bump the shoulder back after every 3rd firing, and for the neck die I use a bushing .003" smaller than loaded round neck thickness. I have never seen the need for a collet resizing die I am not saying you will never need one I just have never needed one.

Montrose
 
I use a Redding Type S Bushing Die as well as the Larry Willis Collet die. As long as you are not having difficult extraction (except for high pressure) or bolt closing you are probably gtg. The Larry Willis die works as advertised and not a bad idea to have on hand. Typically bump the shoulder .002.
 
The LW collet die is only necessary when your brass sticks in the chamber, and you have hard chambering that shoulder bump wont address on a secondary belt that forms in front of the belt. The higher pressure loads you run, the more often you need to use it.
 
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Please excuse my ignorance, I have been reloading for a while also but just bought a die set for 300wm. It's a Redding fl sizer. Does one need more than that?
No you are good in my honest humble opinion. I loaded 300 for about 10 years and mostly used redding type S dies. The Willis die is something I've never needed to use
 
I don't use a Willis die either, but I did have about .025" taken off my Redding Body die so I can size almost all the way to the belt and co-headspace in an A191 chamber. My Winchester bulk got sticky the 7th firing so I just tossed it. That's plenty on cheaper brass sending a 230gr OTM at almost 2800. Why risk a separation for $.50 brass...
 
Mine was a factory remington chamber, some of my brass had 10 firings the first time I needed the LW die some had 2 or 3. It was Winchester brass. I generally use a Lee collet die until they get hard to chamber, then I bump the shoulder with a hornady FL die. I am just getting started again with whatever Criterion cuts their 300wm chambers with.
 
I have .300 winmag brass I’ve fired 10 times that have never been full length sized (necksized only) and still chamber perfectly. I just bump the shoulder 1 or 2 thous and gtg. I had to anneal after 5 firings because neck tension was diminishing and primer pockets are starting to loosen but otherwise fine. Don’t chase the lands too close as pressure will rise dramatically in this case. And yes, beware, case capacity varies greatly beween 300 winny brass manufacturers! Measure your case capacity in grains of h2o! The less you have to resize the better, esp in this case, which tends to stretch and thin out directly above the belt. Many prefer to headspace off the shoulder rather than the belt to minimize stretching. If and when you do full length resize, use a good lube! Those belted cases are stiff and get stuck pretty easily!
 
Best thing you can do is have a smith chuck the barrel in the lathe and move the relief in the chamber for the belt forward about .015" with a boring bar. This negates the belt and lets her headspace off the shoulder like she ought too. Good accuracy gains follow.
 
Best thing you can do is have a smith chuck the barrel in the lathe and move the relief in the chamber for the belt forward about .015" with a boring bar. This negates the belt and lets her headspace off the shoulder like she ought too. Good accuracy gains follow.

Would this leave the case above the belt unsupported in the chamber?
 
Would this leave the case above the belt unsupported in the chamber?
Technically yes, but its still in the web area of the case where it's very thick. Also .015" is only the thickness of a poker playing card. Hardly any. Ive done it to every LR belted mag Ive owned with never a problem. And I load hot..... I have heard lots of people doing this mod. No downsides, all good gains.