Redding die problem

[Nighthawk]

Hey guys, the other day I was reloading for a .338 Lapua and encountered this problem...
I would do the best I could to make the COL to be 3.9" and the first round would always be perfect after my messing with. Problem was every single round I would make would always be at least 10 thousandths off high or low. This would change with each round high or low. To try to fix this problem I would unscrew it a little bit and start from scratch, but I always ended up the same thing, frusteration.

I have this exact same die for a .300 Win Mag and I made 100 rounds a week ago and dame near every one was 3.7" like it was supposed to be.

I tried calling the guy at the realoading place where I bought it and he said he didn't know what the problem was, he recommended that I call Redding. Does anyone out there have a solution before I go hit the phone?

 

[Brent]

Use a tool that measures base to ogive, not the tip. Stoney Point makes one. Tips (meplats) will vary, even the polymer tips aren't even perfect, but much, much closer.

Measuring from the ogive you will see very little difference, if any. Until then just go with the average length, just leave the die locked and don't be moving the stem or you WILL have inconsistancies that greatly effect bullet jam, or distance to the lands.

 

[COBrad]

I agree with Brent, and this might help too. Start again by finding where the bullet is just kissing the lands, then measure OAL of that round. If you know how far you want to be off the lands it will be easy to adjust your die and measure OAL until you have it where you want it. I usually make up a dummy round that just kisses the lands and keep it as a base reference. I would also highly recommend the Stoney Point bullet comparator as mentioned by Brent. I've used one for years and find it to be indispensible.

 

[Nighthawk]

Thanks guys. So now your telling me to spend more money on that huh?

I thought that the bullet should go in the same legnth regardless of the legnth because the die is set at a certain legnth pushing the bullet down into the case? Or am I just stupid? It might be hard to find lands, the barrel has polygonal rifling.

 

[COBrad]

The seating die contacts the bullet at the ogive rather than at the tip of the bullet.

 

[old fart]

Gents - FYI - had a set of dies once years ago ,I was using hunting bullets and a friend of mine gave me some custom , fancy go fast bullets that somebody made , any way , I had to drill out the seating collet thing because the nose of some of the bullets where longer and these would not go in far enough to let bullet seat at the ogee - just a thought

 

[Brent]

Old Fart,
I came close to having to do that one time myself, even my Wilson seater contacts way up high on the VLD type and really should be modified some.

If the tip was contacting before the ogive in his case, he would not be seeing the irregular lengths, but rather they would all be the same from base of the case to the tip of the bullet.

Your bullet is contacting the rifling where the ogive tapers and becomes .338" and your seater stem matches the bullet shape some what to make contact with the ogive up a little higher depending on its radius.

The ogive itself is generally very consistant, so the point where the seater makes contact in relation to where the ogive becomes .338" is generally a very consistant length as a result.

If when you measure the cartridge OAL off of the ogive with a Stoney Point tool or the like and you find inconsistancies, this points to slight/major variations in the ogive shape itself. Without using a different seater stem that contacts in another location on the ogive that is more consistant in length from it to the top of the bearing surface, you will just have to live with any variation or switch to another bullet.

That said, I usually find about 0-.002 variation in OAL at most when using the Stoney Point tool, sometimes .005-.007 with some bullets.

I take an average in this event and seat the longer ones a little deeper into the lands. My referance OAL is always based off the ogive, never the tip. Knowing the OAL to the tip is useful if you are feeding from the mag, but a totally un-neccesary measurement if not.

Neck tension will also vary your OAL to the ogive measurement if the seater plug has enough force on it from the bullet to distort the jacket ANY amount, especially with VLD type bullets. Lighter neck tension will produce shorter OAL's with the same die setting, heavier tension produces longer OAL's.

Finding the distance to the lands is simple and accuarate to the .001 using a split neck case, you might give that a shot before you get too far. Do buy a Stoney Point comparetor to get an acccurate referance length though, it's an invaluable tool.

 

[winmagman]

Nighthawk
Theses loads aren't by any chance compressing the powder are they? Sometimes when the loads are extremly compressed the powder will actually push the bullet back out of the case. Had this problem with H1000 in a 300 win mag, couldn't get consistent OAL to save my butt.
Chris

 

[Nighthawk]

COBrad, I thought that the die touched the bullet at the tip because when I used to load the J40's some of the tips looked as though they were "squashed" a little bit like they were hit in the inside of the die.

Winmagman, the load I was using was 88.6 grains of VV N170 with the 300 gr MK with a supposed OAL of 3.9." This does not seem to be a compressed load.

 

[Nighthawk]

Got a new question for ya. If you were going to make dies for yourself, what would the best place for the die to contact the bullet? Tip, ogive, etc?

 

[Brown Dog]

Nighthawk,
Another possible reason for your original problem maybe overenthusiasm/inconsistency on your bullet seating downstroke on your press.
I had a similar problem once and eventually found this to be the cause.
It was rectified by concentrating on pulling slowly through the 'work' part of the bullet seating and then allowing the press lever to only lightly (and consistently) reach its end-stop (rather than forcing it home).
I reckon that my original firm push at the end of mechanical movement must have been introducing some flex/stretch somewhere in the setup that introduced a degree of OAL inconsistency (I always measure my OAL to the ogive with a comparator).
Hope that may be of help!

 

[Nighthawk]

Thanks, I have always wondered about that myself. I was loading last night for the .300 Win Mag and was thinking of that, but didn't really occur to me because I always just figured that using the press was using the press.