Fire Forming Help

[WSM55]

New project: 6.5x284 Shehane

To expand the standard 6.5x284 Norma case to the 6.5x284 Shehane, it is recommended to JAM the bullet into the land, and fire form the cartridge.
Is it 0.010 into the lands or more? If you seat the bullet to far into the lands, and you need to cycle the cartridge out before firing; you run the risk of the bullet sticking in the lands and dumping powder in the action.

Please help

 

[MagnumManiac]

Your description is why I NEVER fireform with bullets, I use clays (75% case fill) and a twist of toilet tissue. I use 1/4 of a square for 22-250 size cases, 1/2 a square for 308/Roberts/'06/284 size cases and a full square for anything bigger. Give it a partial twist into the case mouth and poke it in with a flat ended dowl/pencil until it's just below the case mouth and is firm, it should squeak a little as you compress it slightly.
To the original question, .010" is as much as I would want the bullet jammed. There is another reason I don't like this method, it can cause excessive case stretching in some rifle designs because the case isn't fully supported. The fireforming method without bullets is gentler on the brass and will give 95%+ of chamber fill with almost 100% headspace for the next firing.

Give this a try, it may surprise you how well it works and you don't waste any barrel life.

Cheers.
gun)

 

[WSM55]

Thanks I will give it a try

 

[WSM55]

75% case fill with clays
What is clays?

 

[dkhunt14]

I don't think you can put powder in like that and form the Shehane. Nothing to hold headspace without a bullet or false shoulder. I always put the bullet in 15 and shot them. After it is chambered you fire it No need to open bolt unless you get a misfire. Matt

 

[MagnumManiac]

Clays is a shotgun powder sold by Hodgdon.
If this case is a blown out version of the 284 case, then you may need to use a false shoulder instead of the bullet jammed. You can look up this method on Google.
Only you will be able to test the different methods, if jamming the bullet, use a mild load in the middle range of powder quickness. It may or may not cause excessive case stretching at the web doing it this way, I know from several hundred examples that my method has NEVER caused excessive stretching, even forming my 375 Weatherby brass from H+H brass.

Cheers.
gun)

 

[WSM55]

Thank you Gentlemen, I really appreciate the help!