Another loading out question

[billbmcleod]

If you have what you think is a good load for a given rifle and the powder level is near 100% capacity or even compressed should you tune down the load when you load the bullet out over book COAL. I realize that the obvious answer is to reduce the load when you change a parameter but I wonder what the effect on pressure actually is to increasing the free space, for lack of a better term. I also suppose the effect depends on how fast burning the powder is.
All input appreciated.

 

[Pr589]

For accuracy you are usually looking for a powder and load near 100% load density. I personally haven't had any issues with compressed loads. The only time I can see it being an issue is at the extreme where the bullet is being pushed up after seating, altering your desired COAL.

This article may be of interest.
https://www.shootingsoftware.com/loadens.htm

 

[Ganderite]

You raise 2 issues:

Compressed loads or 100%. This is a good thing. More air space does not help a load become more accurate.

Loading "bullet out over book COAL". Who cares about the "book" COAL? They did not borrow your rifle, so who cares what COAL they needed for their rifle.

The book COAL might put the bullet into your rifle's rifling, or might position it a long way off. Find the OAL that touches the rifling, make a note of that, then try some tests at that OAL, at 10 thou and 20 thou off the rifling. Those are the numbers that matter for your rifle.

I wish the manuals would put their test OAL in very small print, to give it the significance it deserves.

 

[unstableryan]

I have a tikka t3 in 6.5x55, a long action. Book oal is silly. Magazine has a half inch room and jump to lands is almost that.

It's a great rifle to reload for. Great rifle for deer hunting too.

You raise 2 issues:

Compressed loads or 100%. This is a good thing. More air space does not help a load become more accurate.

Loading "bullet out over book COAL". Who cares about the "book" COAL? They did not borrow your rifle, so who cares what COAL they needed for their rifle.

The book COAL might put the bullet into your rifle's rifling, or might position it a long way off. Find the OAL that touches the rifling, make a note of that, then try some tests at that OAL, at 10 thou and 20 thou off the rifling. Those are the numbers that matter for your rifle.

I wish the manuals would put their test OAL in very small print, to give it the significance it deserves.

 

[ReloaderRick]

If they fit and work. GTG.

 

[VinnyQC]

Actually, if everything else is equal, a longer OAL means more case volume (what you refer to as "free space"), which will generate less pressure. It's shorter OAL that can create overpressure. If a load from a book works well for your rifle if you increase posted OAL, then you got a winner, you've got a good load that will never create overpressure. Load, shoot, enjoy.

 

[bigedp51]

I have a Savage .223 that has a longer throat than my AR15 rifles and can be loaded "warmer" than many manuals.

Make a test cartridge with no primer or powder with the neck reduce in diameter to just hold a bullet. Next seat a bullet "long" and chamber the cartridge and let the rifling seat the bullet and get your OAL.

The ball park figure is .020 off the lands for starters and adjust the for best accuracy. When doing this I would reduce by 10% and work up, seating long can increase your start pressure and increase chamber pressure.

I have fireformed cases by seating long and jamming the bullet into the rifling to hold the rear of the case against the bolt face with out any ill effects. rations

While the link below is for a CZ pistol it has great illustrations and this method also applies to rifles. Read post #3 by Wobbly and look at his great illustrations and written directions.

Topic: How to determine Max OAL for a CZ Pistol (Read 52626 times)

http://www.czfirearms.us/index.php?topic=34225.0

 

[4n2t0]

The manuals should post the following disclaimer:

We used the listed OAL when we tested the load but you have to find your own! lol.

It's probably the most commonly misunderstood aspect of the manuals. I've had people argue that the OAL should never deviate from the one listed in the manual, I tell them that someday they'll be missing a few digits.

 

[VinnyQC]

The manuals should post the following disclaimer:

We used the listed OAL when we tested the load but you have to find your own! lol.

It's probably the most commonly misunderstood aspect of the manuals. I've had people argue that the OAL should never deviate from the one listed in the manual, I tell them that someday they'll be missing a few digits.

Nah, manuals are usually too safe. They'll post a low OAL so that the round chambers in just about every firearm of that calibre, and the maximum powder charge will be safe with that OAL. Accuracy will suffer, mostly.

 

[4n2t0]

Nah, manuals are usually too safe. They'll post a low OAL so that the round chambers in just about every firearm of that calibre, and the maximum powder charge will be safe with that OAL. Accuracy will suffer, mostly.

They rarely list the exact projectile being loaded and that's when "interpretations" can get shady. Like I said, find your own OAL, ALWAYS.

 

[dirtybarry]

One of the best things about reloading is that you can fit your ammunition to your gun, If it fits and works in your gun without any signs of danger then go for it.

 

[RatFink]

The loadings I have been dealing with for my .308 are definitely compressed, where I have had to measure each initial pressing and then adjust the bullet seater depth per load to get them all to a uniform length.
However, when I go for the factory crimp on my TTSXs, they seem to almost be being squeezed outwards since the case mouth is right on the base of one of the cannelures - lengthening the COAL. Does anyone have any words of wisdom to combat that?

 

[Ganderite]

The loadings I have been dealing with for my .308 are definitely compressed, where I have had to measure each initial pressing and then adjust the bullet seater depth per load to get them all to a uniform length.
However, when I go for the factory crimp on my TTSXs, they seem to almost be being squeezed outwards since the case mouth is right on the base of one of the cannelures - lengthening the COAL. Does anyone have any words of wisdom to combat that?

Can you just skip the crimping stage?

I only crimp semi-auto ammo and rifle cases loaded with a light charge of ball power.

 

[RatFink]

Can you just skip the crimping stage?

I only crimp semi-auto ammo and rifle cases loaded with a light charge of ball power.

I'm new to this whole game so I'm only doing what my more experienced friend has said to do... is there any risk of the bullet being jangled in/out of the case without a crimp?

 

[Ganderite]

Not in a bolt rifle.

Don't crimp and test the neck tension by pushing the bullet into the bench. If the bullet slips into the case, you need a crimp. If you can't move it, neck tension alone will do the job.