300 win mag fl resizing problems

[bigfella350]

Hopefully this hasnt been brought up before, and im not just overlooking it somewhere b/c ive only saw slighty similiar problems others have had.
Ive hunted for over 15 yrs now but i didnt get into long range shooting until a yr or so ago & im brand new to reloading besides what ive read & experienced so far, which isnt much.

Ive been saving all my bass & ive bought about 100 once fired casings to start with.
The problem im having is fl resizing the brass id bought online. Im using hollywood dies and a lee single stage "o" type press to do this & ive tried setting the die up the way factory instructions suggest as well as starting the die about. .100 off the shellholder and adding about 1/8 of a turn each time until the casing chambered correctly, bc i dont have a headspacing gauge yet & ive read where alot of ppl have suggested setting your fl die up this way so ur casings shoulder will be fairly close to the head spacing of your rifles chamber.
Neither of these methods have worked for me yet tho & its a little frustrating bc ive tried adding a piece of soda can in the shellholder as well as milling a little off the top of.the shellholder hoping this could be the problem. Neither of these things helped.

I have a savage 110 chambered in 300 win mag and it has a shilen barrel on it & ive never.had an ounce of trouble out of winchester factory ammo. Ive compared casings as well & theonce fired brass' shoulder is almost identical to.the shoulder of my brass thats been fireformed to my rifle. When u throw them side by side u cant tell the difference, but when i set a case ive ran thru the fl die beside them, the resized brass' shoulder is noticeably farther out towards the head, instead of being pushed back lk it should be. I might be making some completely idiotic rookiw mistake and just havent relaized yet but i rly dont think so. I try to be superly thorough in my research and try to take in as much as i possibly can before attempting anything new. I know experience is the only teacher that suffices the job at times but i know this shouldnt be that hard.

So im trying to get some suggestions from some experienced reloaders that might know the cause of this or have heard of this same thing happenong to someone else and what they might have did to fix the problem. Thanks in advance for any advice, it will all be greatly appreciated.

 

[MagnumManiac]

I have loaded for the 300WM and other belted magnums for over 20 years, as you have noticed, the die squeezes the body and the shoulder lengthens, this is normal and happens with all cases, belted or not.
Are you sizing with a gap between the die and shellholder when a case is in the die?
Run a case into the die at full stroke, look to see if there is a gap between the bottom of the die and shellholder, use a torch if it's difficult to see, if there is, turn it in further by 1/16 of a turn until a case chambers in your rifle with a slight feel, then turn it in another 1/32 of a turn. Lock the ring, tighten the set screw and go size all of your cases. Do not turn the die in any more than 1/32 of a turn, it will give you excessive headspace, and I would replace that shellholder with an unmodified one if this is the problem.
Due to sizing forces and press linkage slop, what looks like touching without a case being sized in the die, in fact isn't.
Try this and let us know how you get on.

Cheers.
gun)

 

[bigfella350]

Ok thanks, ill try that this evening when i get home and let u know how it came out.

I bought the dies off gunbroker and they were listed as 300 winchester magnum dies and were being sold by an actual gun store. When i got them in i looked them over and saw the stamping stated 300 mag size die and 300 mag seat die. Im starting to womder if they arent 300 weatherby mag dies now instead. I know hollywood is an older company and the 1st 300 win mag didnt come out until 1963, so could this be why its not stamped win or weatherby because maybe at the time only one 300 magnum cartridge was all that was out at the time?

 

[MagnumManiac]

I doubt that the dies are incorrect, but to check, take an unfired case and try to put it in the die, if it stops roughly the distance that the neck is long, the die is correct for that case.
If it turns out the dies are incorrect, can I suggest you buy a set of new RCBS FL Dies, they are cheap and do the job well.
Let us know how you go.

Cheers.
gun)

 

[bigfella350]

I checked the fl die to make sure & a case starts catching in the die close to what u said it would. Its probably around the length of 1.5 neck lengths or so but still rly close.
I think i finally realized my stupidity in this problem. From what i had read, most ppl didnt have to deal with trimming their brass until after a few resizings, therefore i never once thought about the die being set so low that it was stretching the cases a good 3-5 hundreths. So after it finally clicking in my head, i realized the resized cases were all over max case length. Once i figured this out and shaved a few hundreths off the bolt locked just lk it does when chambering a factory round.
The gunsmith i bought the rifle off of put a brand new shilen s.s. barrel on it for me when i bought it & he said he fired 10 rounds thru it to test his work & that was it. Then since ive had it i havent shot a full 2 boxes thru it yet. So the chamber is probably still very tight. The gun has shot great so far though and once i got it dialed in, ive shot two 3 shot groups at 100 yards that didnt measure over .5-.6moa with factory ammo. So im super stoked about finding a load that it rly likes.& seeing what she will do then.

 

[Don Titus]

I checked the fl die to make sure & a case starts catching in the die close to what u said it would. Its probably around the length of 1.5 neck lengths or so but still rly close.
I think i finally realized my stupidity in this problem. From what i had read, most ppl didnt have to deal with trimming their brass until after a few resizings, therefore i never once thought about the die being set so low that it was stretching the cases a good 3-5 hundreths. So after it finally clicking in my head, i realized the resized cases were all over max case length. Once i figured this out and shaved a few hundreths off the bolt locked just lk it does when chambering a factory round.
The gunsmith i bought the rifle off of put a brand new shilen s.s. barrel on it for me when i bought it & he said he fired 10 rounds thru it to test his work & that was it. Then since ive had it i havent shot a full 2 boxes thru it yet. So the chamber is probably still very tight. The gun has shot great so far though and once i got it dialed in, ive shot two 3 shot groups at 100 yards that didnt measure over .5-.6moa with factory ammo. So im super stoked about finding a load that it rly likes.& seeing what she will do then.

I gave up FL resizing my 300 WM brass a long time ago ... Now just neck size and punch out the primer and "voila" no problems and my brass seems to last forever. As to overall length I suggest you purchase a Hornady comparator ... In my Rem. 700 my head space was 3.575" and so I now load to a COL of 3.565" and it has helped my groups...since the 700 doesn't have a detachable magazine the published length of 3.340" doesn't apply and getting within .005 or .010 of the lands will probably help ... in my case even with max loads, there was no discernible increase in pressures (although in reality I'm sure pressure went up).


Good luck,

Don

 

[MagnumManiac]

Don,
You have mis quoted, your COAL of 3.575" is not a headspace measurement. Headspace is the measurement from the case head to the front of the belt. Belted cases have a headspace .220" +.010". We then change this so our cases headspace off the shoulder, this is how we make our cases last longer.

Blgfella350,
Glad it all worked out for you.

Cheers.
gun)

 

[Marble]

So call me crazy but I recall being told to full length resize the first time around with new brass and then worry about perfection the second loading. Is this not right? It's what I have been doing and I don't have any issues.

 

[MagnumManiac]

So call me crazy but I recall being told to full length resize the first time around with new brass and then worry about perfection the second loading. Is this not right? It's what I have been doing and I don't have any issues.

There is no NEED to FL size new brass, it was done at the factory when it was manufactured, what you NEED to do is NECK size it to make sure it's round, then chamfer the case mouth, inside and out.

You can FL, NECK or PARTIAL FL size after the first firing of new brass, but I would be bumping the shoulder a maximum of .002", this is called PARTIAL FL SIZING, no matter what the rifle is used for, hunting, varminting or target/long range use. This will give the longest case life.

Many people have differing ideas. I used to neck size until cases got hard to chamber, then FL size. I don't do that anymore, now I PARTIAL FL size and my cases last longer than before and I'm not trimming them as frequently, I don't know why, but I think it stems from not sizing the body as much and forcing brass into the neck at the same rate.

Cheers.
gun)