Thread: AOL gauges? Worth it?

Been looking to try and start reloading for accuracy now I have a basic grasp of it. I have loaded about 400 rounds so far, and found that the rifle likes either 39.8 gn, or 41.9gn. I haven't crony'd the loads so I don't know velocitys, but I have picked the lower of the two to help keep the barrel cooler, and prolong the barrel life. Now I have been reading about AOL, and its effects on pressure and accuracy, and am considering going to reloaders and getting the Hornady tool, then I figured there has to be a DIY way to do it. How do you guys measure the AOL, and seat your bullets accordingly. I am about to go measure the magazine, and compare it to the load data in the lee book, and then see how much room I have.

I'd like to hear from some of you guys as to how you measure you AOL.

i use a hornady oal gauge as they are cheap. When i started out i did the old cut the case neck and slight resize, chamber with a projectile in it a little and as you close the bolt it will push into the case. This gives you a in the lands oal

I have done similar after I found something on the net. Lee reloading book tells me that it should be 2.800 in. After I chambered a slightly resized projectile I got 2.850 in, the mag wont allow me to go much past 2.800 but If I go back to the internal mag (i have an aftermarket mag kit for my howa) i can go to about 2.840in. So for accuracys sake, should I work some loads back from 2.840 to 2.800 and see which ones are most accurate? should I do that with different powder weights, or stick to 39.8gn as its a known accurate weight for my rifle/bullet combo. oh and what sort of seating depth increments should i wrok back in? as in, 2.840 - 2.835 - 2.830 - 2.825 etc? or larger increments?

Hey Brennos, if you mean over all length, i use a vernier for my pistol loads, mitre 10, digital $19.99, seems pretty accurate, allthough my pistol rounds arent as fussy, i do use it to make sure im getting consistancy.

I made myself a oal gauge to measure off the ogive but found with plastic tip bullets its just as consistant to measure of the tip,lead tip all over the show.
Id find your just touch the lands lenght and max mag length and start at the shorter and work back fom there unless your into single feeding.

Not quite sure if you are talking about finding your max OAL or accuratly measuring your loaded rounds? To find the oal of the chamber I use the no tools method as Crazyman said but then Ill build a dummy round at that length then seat the bullet deeper in 5 thou steps untill the rifeling leaves no visible marks on the bullet, checking with a magnifier of some sort and polishing off the marks each time.This gives me a startiing length around the just touch point.If that length is to long for the mag and single shot isnt an option then ill start at mag length and go from there. To measure you really need a comparator and callipers.Measuring your loaded round base to ogive is the best option as bullets may vary ogive to tip.How much youll gain will depend on the individual, the set up and what your trying to achieve.

Trying to find the max OAL and the best OAL for my rifle. I have loaded some rounds, starting at 2.810 up to 2.850 in .010 increments, will see how I go from there. Cheers for the replys.

I have recently ordered an OAL gauge from Sinclairs but have been using to date a sized case with a slot cut down the neck (used a hacksaw) to allow the projectile to slide back into the case whilst still maintaining a hold on it. (same effect as partially sizing the neck) Then its a matter of feeding the case with projectile into chamber and slowly closing the bolt.

The idea of the slot is to allow the projectile to be pushed back into the case on contact with the lands without having the lands ride up onto the projectile as can happen with the more pointy high BC bullets.

Then its a matter of extracting the case and measuring with a calipers.

That my 10 cents worth..........

Originally Posted by Brennos

Trying to find the max OAL and the best OAL for my rifle. I have loaded some rounds, starting at 2.810 up to 2.850 in .010 increments, will see how I go from there. Cheers for the replys.

Check for any rifling marks on the pill before you pull the trigger! your sort of going about it a bit backwards,generally you would start at the lands or into them a bit and work back from there. If your load is allready max and you go closer things could get untidy.

2.850 is on the lands. I loaded a pill into a case that was slightly neck sized, and coloured the projectile with a sharpie, chambered it, and measured the over all length of the projectile and case, and went back .010 inches. My longest cartridge is 2.850 the lee book states the cartidge should be 2.800 inches. I guess I'm not explaining my self very well.

Originally Posted by Brennos

2.850 is on the lands. I loaded a pill into a case that was slightly neck sized, and coloured the projectile with a sharpie, chambered it, and measured the over all length of the projectile and case, and went back .010 inches. My longest cartridge is 2.850 the lee book states the cartidge should be 2.800 inches. I guess I'm not explaining my self very well.

Yip sounds good just be aware that pressure will likley increase as you approach the lands. All my loads start at the lands or mag fit and work back from there.
You have loaded at least 3 or better 6 at each lenght all with the same charge? if so one should stand out as a better group hopefully then you can fine tune length either side of it then re tune charge

Originally Posted by veitnamcam

Yip sounds good just be aware that pressure will likley increase as you approach the lands. All my loads start at the lands or mag fit and work back from there.
You have loaded at least 3 or better 6 at each length all with the same charge? if so one should stand out as a better group hopefully then you can fine tune length either side of it then re tune charge

I loaded 5 of each length, at .3 gn above minimum, so hopefully pressure will be ok, Ill definitely be checking every round. I found a while back that my rifle likes either 39.8gn, or 41.9 (.3 above min, and .6 below max) and chose to go with the cooler of the two. Once I find which Length is best, I will probably develop the powder weights again to check they are accurate with the OAL, and then once that's is all sorted I guess ill fine tune the loads a little more. Ill post some results when I go to the range next...

I think people over do reloading. I do NRA shooting and I just googled the best powder and projectile, picked an average powder amount and seat into the lands, job done. Neck size only because it's quicker. My loads seem to shoot just as well as everyone else at the range and I have no OAL gauge or bullet comparator, I don't weigh or sort brass and I have never done any load development. Hunting rounds get alot less attention. Maybe I struck it lucky. I guess alot of people enjoy the development though. I just find the reading wind to be far more effective at reducing group size than load development ever will. Time behind the butt i reckon but i guess you can do both (no pun intended). Just my 2c.