Home Forums Reloading Big Game Rifles Crimping on compressed powder charges

I am having issues with my compressed powder charges pushing the bullet out increasing the OAL, obviously. Bullet lodges in the rifling, pulls out on an unfired cartridge extract dumping the powder in the action, requiring a ram rod to dislodge effectively turning my bolt gun into a single shot.

What issues will crimping present? Increased pressure, affect accuracy?


What issues will crimping prevent? Affecting OAL?

A uniform crimp should help with accuracy if neck tesion was otherwise variable. Can't see it affecting pressure - the engraving of the bullet at the start of the rifling would be significanlty more difficult than the bullet leaving the casing.

Have you tried a longer drop tube when adding powder to the case to minimise the depth of powder in the case and reduce the amount of compression?

If the compressed powder is pushing the bullet out you have touch compression. You can try a drop tube and vibration to settle the powder more. Otherwise reduce the compression

You messing with your 300WSM or one of your 280's? A little hint, take it if you want. All of my dies are set up for a slight crimp. Never have had an issue with bullets backing out, not even from recoil. There are added benefits to loading this way. I'll leave it at that..

Should not increase pressure. Once in a while if your cases are really uneven in length, crimping can hurt accuracy as some cases will get way more crimp than others.

Presuming you've hit your cases with a $5 vibrating toothbrush to settle them, or used drop tube, etc. If not those things can make a lot of room in a case.

You guys using all the trick moves. ha ha..

You may want to check your sizing die too buddy. Sounds like your have very minimal neck tension. That will fu ck with things. What die are your running, if you don't mind me asking. And please don't say competition die or neck sizing die of some sort..

Buy a drop tube.

I was surprised how much less compression I had once I started using a Forster drop tube.

It would too easy to just tell the guy he needs to use a different gun powder....

The cartridge is 308 Winchester. Lapua cases right out of the box, no sizing. 48.5 gr Varget under a 155 Scenar. During initial load development this worked so well until began dumping powder in the action about every fifth unloading extraction. I know, it’s unorthodox not to presize your cases, but it was working so well until it did not.

Tried my drop tube, tapping the case on the bench but none of it worked. Did not consider vibrating the case.

This load, for the times I got it down to 2.335 oal shot so accurately and functioned so well it was love at first shot. Currently it seems “that” Elvis has left the building.

My dies are Redding Type S. Believe it or not, i have not even used them. Been seating with my Wilson die.

How did you arrive at that charge? It seems a bit on the hot side.

+1. I punched that load into QL without touching the OAL and gave me 76K.

Top load in the Nosler book. Does not cause any issues in my gun. No extraction problems, no flattened primers, just creeping OAL from the compression. And, several dead critters, no problem.

Switch to norma brass for that load. It has more internal volume than the domestic varieties.

That load was established in the Nosler book years ago when they used thin, capacious Winchester brass for the 308 loads. There is no way they re-shot that data and got the exact same velocities in Nosler brass as indicated in later manuals. Simply no way. On top of that I'm looking at a picture which shows the 155 Scenar to be as long as a 175 Match King which will eat case capacity compared to more conventional 150/155 grain bullets.

P

308 Winchester in my Sako 85. The gun is very accurate with this load and it averages 2880 fps. Never considered setting the die for crimp. You may be onto something there.