Thread: Remington 700 Sako and M16 extractor conversions

Originally Posted by kimjon

I think the issue is that some people believe that loading manuals are ''playing it safe'' and that hard brass is safe beyond the stated values as they don’t exhibit pressure signs.

For one reason or another squeezing an extra 100fps out of an already fast rifle at unsafe pressures appears to make sense to them? However I can see no tangible gain in obtaining that extra 100fps at the cost of brass life and having an unsafe rifle.

Stick to the safe loads and it won’t be an issue. And unless you have pressure measuring equipment, a loading manual is about all we have to go on...anything else is just a stab in the dark.

kj

So if the manual says for instance 46grmax of whatever for 2900fps and I only get 2600fps am I being reckless in going over max?

Originally Posted by veitnamcam

So if the manual says for instance 46grmax of whatever for 2900fps and I only get 2600fps am I being reckless in going over max?

Hell no, you load to the same velocity, then you'll be getting the same pressure as the loading manual load. I wrote an extensive reloading series on this back a few issues. You may take more or less powder to equal the same velocity and pressure, depending on your individual rifle's chamber and barrel specs. The velocity is your best guide to pressure if you don't have pressure testing equipment. Just be sure you're comparing like with like, eg same barrel length - minor chamber dimension variations don't matter.

Originally Posted by Greg Duley

Hell no, you load to the same velocity, then you'll be getting the same pressure as the loading manual load. I wrote an extensive reloading series on this back a few issues. You may take more or less powder to equal the same velocity and pressure, depending on your individual rifle's chamber and barrel specs. The velocity is your best guide to pressure if you don't have pressure testing equipment. Just be sure you're comparing like with like, eg same barrel length - minor chamber dimension variations don't matter.

Just the answer I was looking for.....................there are those that will not go over book max even if their hand load is well below factory ammo velocity's and the rest of us.

Originally Posted by Greg Duley

Hell no, you load to the same velocity, then you'll be getting the same pressure as the loading manual load. I wrote an extensive reloading series on this back a few issues. You may take more or less powder to equal the same velocity and pressure, depending on your individual rifle's chamber and barrel specs. The velocity is your best guide to pressure if you don't have pressure testing equipment. Just be sure you're comparing like with like, eg same barrel length - minor chamber dimension variations don't matter.

So if you swap out a barrel, with the same chamber specs, and need 4 more grains to acheive the same speed with all variables being equal, are you saying that chamber pressure is the same on both?

Originally Posted by Spanners

So if you swap out a barrel, with the same chamber specs, and need 4 more grains to acheive the same speed with all variables being equal, are you saying that chamber pressure is the same on both?

That's what I was getting at Spanners. Physically speaking it just isn't possible.

Originally Posted by veitnamcam
So if the manual says for instance 46grmax of whatever for 2900fps and I only get 2600fps am I being reckless in going over max?


That's a good question and one that neither of us can answer without the correct tools to measure the pressure, in this case your guess is as good as mine.

Some barrels are tight and produce high pressure-low velocity. Others are loose and produce high velocity-less pressure for the same load. Just look at what a difference seating death can do to pressure by simply altering it by 10thou.

I'm sure you already know this but pressure increases dramatically with those last few grains powder, it’s not a linier equation that you can extrapolate from tables more an uncontrolled spike that happens when you go past a point of no return. Sure the manuals will be conservative, they have to be in order to avoid people from killing themselves, but if you want to push it to the limit it’s a fine line and it’s going to come at a cost (minor - brass, barrel wear or major - a catastrophic failure?).

Knowing what that limit is without a way of measuring the pressure makes it simply a guess a best doesn't it?

kj