OAL check or not?
- Thread starter bolski
- Start date
DannoBoone
Active member
Back in the '60's when I started reloading, we had never heard
of such a thing as an OAL gauge and still got plenty of prairie
dogs and deer with 22-250's and 25-06. Even up to 20 years ago,
I had never heard of one....just used calipers to measure OAL,
but nothing to measure off the ogive. But after hearing about
it, and acquiring one, I can testify that it does make quite a
bit of difference when going for tiny groups on paper. So it
depends on what you are attempting. I don't believe a prairie
dog is going to know the difference if you are 1/4" off @ 100yds,
but he might be laughing at you at 500yds.
of such a thing as an OAL gauge and still got plenty of prairie
dogs and deer with 22-250's and 25-06. Even up to 20 years ago,
I had never heard of one....just used calipers to measure OAL,
but nothing to measure off the ogive. But after hearing about
it, and acquiring one, I can testify that it does make quite a
bit of difference when going for tiny groups on paper. So it
depends on what you are attempting. I don't believe a prairie
dog is going to know the difference if you are 1/4" off @ 100yds,
but he might be laughing at you at 500yds.
muskrat30
New member
Just about all of those 500 yrd prairie dogs laugh at me. We really hit it right a few years back in SD. The time was mid June & got into a seldom hunted town. There were a good amount of targets from 50-175 yards.
The 'guide' asked me when I was taking my time, 'don't you see those out there'? I said yes I do, but in a few more seconds I'll have one at 100 yrds. I had to let the gun cool anyway.
The 'guide' asked me when I was taking my time, 'don't you see those out there'? I said yes I do, but in a few more seconds I'll have one at 100 yrds. I had to let the gun cool anyway.
CatShooter
New member
Originally Posted By: muskrat30
" There were a good amount of targets from 50-175 yards."
50-175 yards??... that's where the girls shoot Prairie Doggies
" There were a good amount of targets from 50-175 yards."
50-175 yards??... that's where the girls shoot Prairie Doggies
muskrat30
New member
Originally Posted By: CatShooterOriginally Posted By: muskrat30
" There were a good amount of targets from 50-175 yards."
50-175 yards??... that's where the girls shoot Prairie Doggies
I was hunting in IL a few years back. I had a handful of anterless tags on a prime private farm. I was stacking em up with my Knight. My buddy commented on my shooting skills. Without taking to much away I didn't go into my real methodology. Those methods included allowing that 150+ yrd deer to become a 75 yrd shot. This was providing the winds were cooperative to allow.
Can't help it with the prairie dogs, I've only been twice & like to see & hear a splat.
" There were a good amount of targets from 50-175 yards."
50-175 yards??... that's where the girls shoot Prairie Doggies
I was hunting in IL a few years back. I had a handful of anterless tags on a prime private farm. I was stacking em up with my Knight. My buddy commented on my shooting skills. Without taking to much away I didn't go into my real methodology. Those methods included allowing that 150+ yrd deer to become a 75 yrd shot. This was providing the winds were cooperative to allow.
Can't help it with the prairie dogs, I've only been twice & like to see & hear a splat.
Ackman
New member
Don't know what you mean by OAL gauge.....you measure that with calipers. And OAL is irrelevant anyway except if there's a magazine length problem. If you're talking about ogive length - casehead to bullet ogive, the part that touches the lands - then yes you should absolutely have one of those gauges for each caliber you shoot. Davidson makes one that attaches to the caliper beam, Sinclair sells them.
Dial caliper and attachment that fits on the ogive of the bullet is really critical for attaining the best accuracy out of your rifle.
www.sinclairintl.com has a Davidson ogive gage that is caliber specific that fits on the fixed blade of a dial caliper. Used in combo with a split neck case, is the most accurate way to get the measurement from bolt fact to bullet contact with lands that I have used(I have used all methods). The Davidson ogive gage is $17, but it once and pass it down to your grand kids.
If you are not measuring and working up loads to the OAL that your rifle prefers, you are walking in the dark when it comes to achieving your rifle's best accuracy. Wake up America!
www.sinclairintl.com has a Davidson ogive gage that is caliber specific that fits on the fixed blade of a dial caliper. Used in combo with a split neck case, is the most accurate way to get the measurement from bolt fact to bullet contact with lands that I have used(I have used all methods). The Davidson ogive gage is $17, but it once and pass it down to your grand kids.
If you are not measuring and working up loads to the OAL that your rifle prefers, you are walking in the dark when it comes to achieving your rifle's best accuracy. Wake up America!
I use a technique that is similar to the Sinclair system and recommend it for anyone who would prefer to make their own instead of buying a retail OAL measurement system.
I'll be brief but hopefully you will get the idea.
Using your cleaning rod and a couple of collars with set screws installed on it You can take measurements of the distance from the tip of the muzzle to the bolt face. Then drop a bullet in the chamber and take a measurement from the muzzle to the tip of the bullet.
The difference in those two measurements will give you the max length of a round that will touch the lands with a specific bullet.
Use the two collars exactly like the ones on the Sinclair guage. The distance between the collars is the max OAL of that bullet.
Making the collars is pretty easy. I used 2 delrin tubes I picked up at the hardware store. I also bought 2 threaded bushings and thumb screws to install into the side of the collars. Cost was betwen $5 -$10 for the completed collars and took about 10 minutes to drill the collars and install the threaded bushings. I also took a spare jag and grund it flat on the end and use that on the tip of the cleaning rod.
When you measure the distance to the bullet tip, keep that exact same bullet and use it to make your dummy cartridge. All bullets are not identical and this insures you can get your dummy round set.
The best way to double check your measurements is to seat that bullet as the dmmy round a little long and when you chamber that round you should find that it is long and hits the lands. I usually seat it 0.002 longer than the measurement, just to insure that I have a little crush fit. As soon as I can verify the case is long, I will seat it to the depth I decide to use and then my seating die is set and ready.
Keep the dummy for setting up new rounds at a later date. Remember that dummy round is only good for that specific bullet model. If you change bullets, you neeed to make a new dummy round.
I'll be brief but hopefully you will get the idea.
Using your cleaning rod and a couple of collars with set screws installed on it You can take measurements of the distance from the tip of the muzzle to the bolt face. Then drop a bullet in the chamber and take a measurement from the muzzle to the tip of the bullet.
The difference in those two measurements will give you the max length of a round that will touch the lands with a specific bullet.
Use the two collars exactly like the ones on the Sinclair guage. The distance between the collars is the max OAL of that bullet.
Making the collars is pretty easy. I used 2 delrin tubes I picked up at the hardware store. I also bought 2 threaded bushings and thumb screws to install into the side of the collars. Cost was betwen $5 -$10 for the completed collars and took about 10 minutes to drill the collars and install the threaded bushings. I also took a spare jag and grund it flat on the end and use that on the tip of the cleaning rod.
When you measure the distance to the bullet tip, keep that exact same bullet and use it to make your dummy cartridge. All bullets are not identical and this insures you can get your dummy round set.
The best way to double check your measurements is to seat that bullet as the dmmy round a little long and when you chamber that round you should find that it is long and hits the lands. I usually seat it 0.002 longer than the measurement, just to insure that I have a little crush fit. As soon as I can verify the case is long, I will seat it to the depth I decide to use and then my seating die is set and ready.
Keep the dummy for setting up new rounds at a later date. Remember that dummy round is only good for that specific bullet model. If you change bullets, you neeed to make a new dummy round.
Varminterror
New member
Seems to me that finding proper coal for a given bullet must be a lot mor difficult than I thought it was? All I ever do is neck size so my brass will hold a bullet, put my bullet of choice in the neck, either soot with a match, or paint with a magic marker, slowly and carefully chamber the round. Wen I pull it out, I can either see the rifling impressions, or the bullet wasn't hanging out long enough (or I didn't have enough neck tension and it was seated by the lands to the proper depth). I go through that 3-5 times to make sure I get consistent numbers, then pick my desired 'Jump'.
I keep notes in my manuals of how long my coal with a given bullet will be with each rifle I'm using it in, so I know as I tune my coal for load development that I have to be careful if I meet or exceed that length. I use different brass and different bullets for different rifles of the same caliber so I know I can't accidentally over-pressure one specific rifle by using a different rifle's load.
In general, 'specs' you'll find in manuals will be a safe load for any factory rifle, short enough that they won't make contact with the rifling, so yes, that's a safe length to use. But being that short, you may not be happy with the accuracy from excessive jump.
I keep notes in my manuals of how long my coal with a given bullet will be with each rifle I'm using it in, so I know as I tune my coal for load development that I have to be careful if I meet or exceed that length. I use different brass and different bullets for different rifles of the same caliber so I know I can't accidentally over-pressure one specific rifle by using a different rifle's load.
In general, 'specs' you'll find in manuals will be a safe load for any factory rifle, short enough that they won't make contact with the rifling, so yes, that's a safe length to use. But being that short, you may not be happy with the accuracy from excessive jump.
