K31 Reloading help again! Bullets are too big?

[onlycrimson]

Alright, so according to a couple manuals and of course the recommendations here I used the .308" bullet for my k31 reloading. I'm using 150gr. winchester boat tails.
Today I went to the range to try a few out and upon loading the cartridge noticed that the bolt would not lock, this is normal for some hand loads, even if they are full length sized as these were. So I pushed harder and could not get the round chambered. I pulled the bolt back and the round came apart on me with the bullet stuck in the chamber. So I used a cleaning rod and pounded it out. I noticed that the bullet had scratched on it from trying to be forced in. So I tried another hand load and it also did not work. I then grabbed my friends k31 and it also had the same issue. I went home and slugged the bores of the rifles and they are .305".
I'm not sure what to do here. The other dimensions of the cartridge were all within spec. Measuring PP and GP11 the bullet sizes were .306" and .300" respectively. Any recommendations?

Information

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[gunner]

How long is your OAL? Measure out how long the complete round can be and set it 0.5mm shorter. That sounds to me as if the round were to long. I always used .308 bullets in my Swiss rifles and never had any problem with it. Dont make it longer than 75,5mm or 2.972

[Latigo]

And......... it could very easily be your case is not full length sized correctly and trimmed to length. That is the primary reason for what you're describing.

Latigo

[onlycrimson]

Ok, I will double check these measurements and post back.

[onlycrimson]

Ok, I took some measurements. Case length- 2.189", neck diameter-.333", case diameter at base- .494" and for OAL I used two different lengths-2.953" and 2.996".

[Latigo]

But are you full length sizing? Also your OAL changes from bullet profile to bullet profile. The correct length is going to be determined by where your bullet ogive contacts the lands/grooves, not the meaurement from base to bullet tip. A mfg. will post an OAL based on their bullet, but that OAL won't be the same for a different profile bullet from a different mfg. You need to do a seat depth test.
Check here. Reloading for Beginners. in SwissProducts Discussion and Support Forum

That might help.

Latigo

[Latigo]

I forgot to mention the obvious. If your projectile is sticking in the lands/grooves, it's certain that your seat depth is wrong. Forget all about posted OAL's in your manuals. Do a seat depth test and then back the bullet off by another two thousandth's. K31's like very little freebore.

Latigo

[gunner]

I forgot to mention the obvious. If your projectile is sticking in the lands/grooves, it's certain that your seat depth is wrong. Forget all about posted OAL's in your manuals. Do a seat depth test and then back the bullet off by another two thousandth's. K31's like very little freebore.

Latigo

Haven´t i said this?

[Latigo]

Yeah, but nobody reads your posts Gunner.

[Latigo]

Gunner, you're not quite in the ballpark. The cartridge OAL will have little to do with the bullet sticking in the lands/grooves if the ogive is closer to the tip than a different profile bullet. IE: A Hornady has a shorter nose than a Berger VLD, so the OAL will definitely be shorter.