Cheap OAL tool

Ganderite

Ganderite

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Farm south of North Bay
I call this my OAL Hat.

If I want to load my rifles at, say 20 thou off the rifling, it takes a bit of fiddling to get that seating depth. Then I put the "hat" on the bullet and measure from the case base to the top of the hat. the hat is a one inch piece of rifle barrel.

Since the hat is sitting on the bullet ogive, that distance will be a constant, regardless of the shape and length of other bullets I might load for that rifle.

My log book shows the hat size for each rifle.

Your friendly gunsmith has a junk bin of old barrels. Just ask him to slice you a piece.

OALHAT.jpg
 
Suputin said:
That works for measuring the loaded round but how do you measure the distance to the lands in your rifle? You can't load rounds to a specific distance from the lands if you don't know the distance to the lands.
Click to expand...

Well you make a dummy round that DOES touch the rifling and THEN use the above OAL gauge to add/subtract/repeat the OAL for your loading.

This works the same as the Hornady OAL gauge but basically for free.


Jim, do you use partial barrels for each caliber you load or did you just use a piece of barrel from a .22cal that ensures it will hit the ogive somewhere on all calibers?
 
When a rifle barrel is manufactured, it is bell mouthed at both ends. The chamber end does not matter, because it is reamed out a couple of inches for the chamber. The muzzle end is circumsized about one inch.

The barrel maker's scrap bucket is full of those I inch "hats". Grab one in each caliber. For some of them I ran my chambering reamer into the hat so the throat in the hat is the same as the one in the rifle. That does not matter, because all we want is a constant way to transfer ogive position from one load to the next.

Or, one can take a large nut and drill a series of holes into each flat, to approximate bore diamater of a variety of calibers.

OALMULTIHAT.jpg
 
Ganderite said:
When a rifle barrel is manufactured, it is bell mouthed at both ends. The chamber end does not matter, because it is reamed out a couple of inches for the chamber. The muzzle end is circumsized about one inch.

The barrel maker's scrap bucket is full of those I inch "hats". Grab one in each caliber. For some of them I ran my chambering reamer into the hat so the throat in the hat is the same as the one in the rifle. That does not matter, because all we want is a constant way to transfer ogive position from one load to the next.

Or, one can take a large nut and drill a series of holes into each flat, to approximate bore diamater of a variety of calibers.

OALMULTIHAT.jpg
Click to expand...

what would the dimensions of the holes be,ie for 30 cal. would it .308 or the diameter of the barrel without the rifling grooves( I can't remember that dimension right now but I have it somewhere)thanks in advance john p
 
Easier still... Seat the bullet (in an empty/unprimed case) to standard spec, then paint the bullet with a magic marker. Pull the bullet out in increments and chamber the dummy round until you see rifling marks on the bullet, then if you want .20 thou off the lands for example, simply seat .20 thou deeper.
Doesn't get much more simple than that. ;)
 
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