I am new to reloading and I have a question for anybody - All loads talk about OAL. However people also talk about getting bullet just of rifle lands. When I get bullet .020 off my lands in 300 win mag my OAL is longer than that listed in reloader manuals. Is the OAL in manuals just a guide line?

Thanks for the help

If it is longer than listed in the loading manual you will be reducing pressure which is fine but the other limiting factor here is magazine length and this varies among different makes even with the same chambering.

For best accuracy loading just off the lands is good advice but the loaded round also needs to cycle through the magazine (unless you want to use it as a single shot). Work out what will work as the max OAL that will feed through your magazine and as long as you dont exceed that, then load just off the lands.

Hope this helps.

[quote]"Is the OAL in manuals just a guide line?"

Basically. It's the length the fellow who developed the load data used. It's not really relivant for rifles but it's a good starting point for beginners. It is more significant with handguns tho, much longer may not chamber and shorter will raise pressures somewhat.

Actually, the COAL is primarily limited by the need to feed from a magazine. Some rifles have shorter magazines than others but the book figures given will usually work in most guns. Most folks seat cannalured bullets in the groove and live with that.

Don't sweat trying to get your bullets into the lands, many rifles shoot better with 10 to 40 thousants jump to the lands. And that figure is based on the clearance to the bullets ogive (curve) and not the pointy end! Round noses will hit the lands sooner than the long tapers will if the COAL is the same. If your ammo functions and shoots good don't sweat it.

Over time you will see that a lot of information here varies depending on what type of shooting you do. If you become a BR shooter then a lot of little things make little bitty changes. If you are just a hunter then a lot of what you read here on reloading does not apply. Experience will tell you the difference over time.

quote:

Originally posted by Willis Vandenberg:
I am new to reloading and I have a question for anybody - All loads talk about OAL. However people also talk about getting bullet just of rifle lands. When I get bullet .020 off my lands in 300 win mag my OAL is longer than that listed in reloader manuals. Is the OAL in manuals just a guide line?

Thanks for the help

The OAL established by the ammunition industry (SAAMI) is merely a guideline for us handloaders. This is because all rifles are individuals, and what may prove to be a perfect OAL for one gun using a particular set of components may prove to be too long or too short for another.

For example, one rifle may shoot best with a given powder charge and bullet with the bullet seated out to almost touch, or actually touching, the rifling. However, some other bullet/powder charge combination in that same gun might require an entirely different seating depth.

And, if you are loading for a rifle with a box magazine, the rounds can't be too long or they won't work in the magazine, but this is not a problem for a person loading for a single shot, etc. etc. And each powder charge/bullet combination for a given individual rifle may be different in OAL from every other load for that rifle. And so on, ad nauseum!

OAL is a SAAMI standardization. The advantage of being a handlaoder includes setting loads up for you particular chamber. The chamber in your .300 Winny is slightly different than another .300 from the same manufacture.

Good question.