The Firing Line Forums - View Single Post - hand loads for a 30-06, 308, 22-250 rifles

Bart B. · June 1, 2012, 07:10 AM

In my experience, there's two main reasons why the bolt binds trying to extract a fired bottleneck case from a chamber.

One's when peak pressure's way too high. Often happens with folks loading belted cases as they want every foot per second of velocity they can get. They put as much powder in the case as they can that doesn't show pressure signs as they look at fired cases and primers or measure case expansion. But looking at and measuring fired cases is a poor way to judge pressure, especially if the chamber's quite a bit larger than the case and the hole in the bolt face is much larger than the firing pin tip diameter.

Another's when neck only sizing's been done and after several shoot and resize cycles, the case has expanded enough that it's case head binds against the bolt face 'cause they're both not square enough. This happens typically when the bolt face ain't square with the chamber axis; very common with factory rifles; more common in service rifles.

Regarding how fired cases are sized, yes, full length size them. Benchresters started switching over to full length sizing some years ago. Sierra Bullets' full length sizes all their cases used to test their stuff for accuracy. High power match rifle competitors winning matches and setting records with both the .30-06 and .308 Win. full length sized their fired cases, too. The .22-250's not any different. It's important that the case body diameters not be reduced more than a couple thousandths as well as the case neck be set back no more that that amount, too. Best accuracy tyically comes with full length sizing dies with a bushing in them that's a couple thousandths smaller than a loaded round's neck diameter. Deprime your fired cases in a separate die first, then tumble/vibrate them clean, lube and resize them. This makes for much straighter case necks as no expander ball's used that typically bends case necks too much. For what it's worth, both full length and neck only sized bottleneck cases center up front in the chamber equally accurate aligning the bullet very well with the bore when fired. The advantage of full length sizing fired cases is it eliminates any interference between case body and chamber body as neither one is perfectly round. And it makes for much easier fired case extraction from the chamber.

June 1, 2012, 07:10 AM	#11
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	In my experience, there's two main reasons why the bolt binds trying to extract a fired bottleneck case from a chamber. One's when peak pressure's way too high. Often happens with folks loading belted cases as they want every foot per second of velocity they can get. They put as much powder in the case as they can that doesn't show pressure signs as they look at fired cases and primers or measure case expansion. But looking at and measuring fired cases is a poor way to judge pressure, especially if the chamber's quite a bit larger than the case and the hole in the bolt face is much larger than the firing pin tip diameter. Another's when neck only sizing's been done and after several shoot and resize cycles, the case has expanded enough that it's case head binds against the bolt face 'cause they're both not square enough. This happens typically when the bolt face ain't square with the chamber axis; very common with factory rifles; more common in service rifles. Regarding how fired cases are sized, yes, full length size them. Benchresters started switching over to full length sizing some years ago. Sierra Bullets' full length sizes all their cases used to test their stuff for accuracy. High power match rifle competitors winning matches and setting records with both the .30-06 and .308 Win. full length sized their fired cases, too. The .22-250's not any different. It's important that the case body diameters not be reduced more than a couple thousandths as well as the case neck be set back no more that that amount, too. Best accuracy tyically comes with full length sizing dies with a bushing in them that's a couple thousandths smaller than a loaded round's neck diameter. Deprime your fired cases in a separate die first, then tumble/vibrate them clean, lube and resize them. This makes for much straighter case necks as no expander ball's used that typically bends case necks too much. For what it's worth, both full length and neck only sized bottleneck cases center up front in the chamber equally accurate aligning the bullet very well with the bore when fired. The advantage of full length sizing fired cases is it eliminates any interference between case body and chamber body as neither one is perfectly round. And it makes for much easier fired case extraction from the chamber.