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cpatbay
07-20-2012, 7:05 PM
I am reloading some 45 ACP using Nosler 185gr JHP with Vihtauvouri N320 powder. From Vihtauvouri web site, the reloading data published is with an COL of 1.130". I tried to follow this but could only got to 1.169" and it's already looking "too short". By too short, I mean the curved part of the bullet is going to go below the case edge if I push it in more. Has anyone had this observation with this loading? Is it really correct to go down to 1.130"?

sofbak
07-20-2012, 7:18 PM
My Lee manual lists the same COL for your load combination.

Maybe a dumb question, but are you sure you're loading a 185 gr. projectile? I have a lot of 230 gr. commercial rounds, and they are all much longer-in the range of 1.260

cpatbay
07-20-2012, 7:22 PM
Yes, I checked. it's the 185gr that I am loading. I don't even have any 230gr bullets ...

sofbak
07-20-2012, 7:35 PM
OK. Next dumb question: Assuming your using a set of calipers-are they properly zeroed? On the digital models, its possible to hit the "zero" button accidentally, and if the calipers are open any at that time, you will get a reading that is longer than actual by whatever the open distance was when the button got "fat fingered".

Bill Steele
07-20-2012, 7:49 PM
First, the COL in a load spec is a minimum, you can load as long as you want, just not shorter than the published OAL in the load spec.

Second, that is probably a typo, load it more like 1.235", just don't load over 6grs and you should be fine.

sofbak
07-20-2012, 8:26 PM
So the published COL is the minimum for that specific combination of projectile and powder?

I noticed in an Alliant manual and a Hogdon manual that for that weight/type of projectile, they each have COL's that are different from the Vi and Lee manuals.

All the Hogdon powders use the same COL, but in the Alliant manual, COLs vary from powder to powder. No wonder reloaders keep a "notebook".

Would it be safe to just use the cartidge COL on the standard SAMMI drawing?

Bill Steele
07-20-2012, 8:52 PM
So the published COL is the minimum for that specific combination of projectile and powder?

I noticed in an Alliant manual and a Hogdon manual that for that weight/type of projectile, they each have COL's that are different from the Vi and Lee manuals.

All the Hogdon powders use the same COL, but in the Alliant manual, COLs vary from powder to powder. No wonder reloaders keep a "notebook".

Would it be safe to just use the cartidge COL on the standard SAMMI drawing?

When someone publishes a load, they publish an OAL. The OAL in the load spec is a known safe seating depth for that bullet and powder charge combination (assuming, of course, the numbers in the load are not typo's, this is why consulting multiple sources and using the most conservative to start is a good idea). It doesn't mean shorter OAL's will be unsafe, it just means for that load using that OAL or longer will result in safe pressures. Obviously the caveat is the max listed load may or may not be safe in your specific gun, so you still have to work up from start levels.

Many of the books are just transcribed data from bullet or powder manufacturer actual tests. The reason you get different OAL's or different max loads, etc. are the result of the tests the different companies got when testing.

It is best not to use a flat rule of thumb for any loading. Getting to know a given caliber, powder and bullet combination and how they work in a given gun is the best approach.

Have fun, good luck.

sofbak
07-20-2012, 9:23 PM
...... It doesn't mean shorter OAL's will be unsafe, it just means for that load using that OAL or longer will result in safe pressures. Obviously the caveat is the max listed load may or may not be safe in your specific gun, so you still have to work up from start levels.
.....

What I was thinking of was function in a semi-auto gun. I would hate to load up a bunch of rds to a listed short COL and then find that they won't feed:(

My reasoning was (as you said) the longer COL will be safe, and with the SAAMI spec dimension for COL both should ensure that:

A. I have a safe load.
B. It should feed through a normally functioning gun of that caliber.Is that reasonable?

Bill Steele
07-20-2012, 9:45 PM
What I was thinking of was function in a semi-auto gun. I would hate to load up a bunch of rds to a listed short COL and then find that they won't feed:(

My reasoning was (as you said) the longer COL will be safe, and with the SAAMI spec dimension for COL both should ensure that:

A. I have a safe load.
B. It should feed through a normally functioning gun of that caliber.Is that reasonable?


Sure. Many times (but not always) semi's like OALs on the longer side. This of course is from a feeding perspective just to the point of the gun going into battery, at that point, depending on the bullet profile, the type of bullet and it's dimensions (i.e. cast, jacketed,etc.), the dimensions of the throat, it's freebore, etc. etc. you might run into chambering issues with OALs on the longer side.

The more I reload, the more I appreciate commercial loaders, reloading equipment suppliers, etc. It is an ocean of tolerance buildups, picking things so they work in everyone's gun (more often than not) is a real art form.

That is why it always cracks me up when somebody comes on these threads and makes a blanket statement about some element of reloading full of subtle tradeoffs. It is the quickest way to identify someone who knows little about the subject of reloading, the more blanket statements they make.

sjg1966
07-21-2012, 3:32 AM
FWIW....I load 185gr Berry's plated flat point to 1.20" COL for use in my Sig P220s.