measuring o.a.l in my rifle

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Deadeyejedi

Deadeyejedi

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ive been trying to determine the correct oal in my sons cva scout 243. i have several discrepancies to discuss.By following the proper procedure for measuring i come up with an oal of 2.768 with a 105gr hornady bthp,an oal of 2.630 for the hornady 100gr btsp(incidentally this falls about .040 short of the cannelure).the factory remington corelokt 100gr measure in at an oal of 2.700 avg.and the factory fusion comes in at 2.598.the method i used was by putting a bullet in a once fired case and inserting it in the gun closing the action then carefully removing it and measure ,then subtracting .015 from that measurement.i did many times so as not to get a false reading .what are your thoughts?
 
That works for a quick and dirty if you're careful. The Hornady OAL gauges also work very well and aren't too costly until you have to buy their OAL cartridges for 30 calibers that you're reloading.
 
I’ve researched the guage but it looks another one of those things where the gun determines what it likes.some like more space in that area than others .I do know the stuff I load with cannalures are the shortest of the lot and turns out the least accurate maybe this is why.I’ve also read that seated in the land or very close shoots more accurately
 
I second the Hornady gauges. If you load for more than a couple of guns they are worth it.
Measuring with a case and a bullet works ok, but, is hardly precise. As you probably learned it is a bit of a pain.

OAL varies depending on the bullet as the ogive is different from different styles. Here is something I used to do. If you have a factory load that shoots well set the seating stem on your die to just touch the bullet. Then use the die with that setting for your hand loads. As long as it still will cycle in the action accuracy will usually be at least decent.

Don’t seat hunting ammo to the lands. At least .020 is my minimum. If seated to the lands, sooner or later, you will have one just a bit to long and the bullet will pull out when the cartridge is removed from the chamber. Powder then goes everywhere . It happened to a friend and that’s the story I’m sticking to lol.
 
I use the Sinclair bullet seating tool. It is available from Brownells.
 
WeekendReloader said:
I've taken a sized case and slit the neck with a dremmel tool cutting disk. Then place a bullet in and insert into the chamber. You can pinch the slit neck a little to give more tension on the bullet if you need it.
Click to expand...

This is exactly what I do. Has been working well for me!
 
I see a lot of effort and time put into a measurement in and of itself adds no value. The seating depth test gives you data by which to make a decision that matters. Run the Berger seating depth test and a sloppy max oal is all that is required to give a a starting point. If your seating and crimping into a canalure you maximum seating spread is unaffected by max oal for that bullet.
 
The stoney point hornady tools are a quick easy way but I've most times found they actually give you a bit shorter COL if anything. They are spacing based on the shoulder so you're counting on that case matching your chamber exact which it won't unless you are making a case from your fired unsized brass.

The most accurate way is to take the extractor out of your bolt and keep seating a bullet a little at a time until you can feel it close with tiny bit of caming force to close the bolt. making sure the piece of brass you are using has no resistance prior to seating a bullet.

Personally I don't think it's necessary to worry about that accurate of measurement. Just so I know I'm short enough not to stick a bullet in the barrel I'm good. Somewhere from that point back is where you are going to find your best seating depth anyway.
 
I take the ejector and firing pin assembly out of my bolt and start long, dropping.005 at a time until the bolt will drop with zero resistance. There used to be a great utube video showing this, but I can’t find it anymore .

That gets me my starting point, and I have stayed there even as the lands have started washing out. I loaded my Dasher .010 to .015 off the lands with a nice new barrel, and have stayed with the same base to ogive length/seater setting.
 
Yes, you can. I have been using a Whidden "Case Gauge" to set up my sizers for 6 Dasher & 6 Creed, but lots of ways work. They have comparators as well. I use the Sinclair comparators.
 

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  • Sinclair Comparator Body, .22, 6MM, .30 Cal inserts, 30 Degree Shoulder Insert @ 40%.JPG
    Sinclair Comparator Body, .22, 6MM, .30 Cal inserts, 30 Degree Shoulder Insert @ 40%.JPG
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  • Whidden 6 Dasher Case Guage @ 50%.JPG
    Whidden 6 Dasher Case Guage @ 50%.JPG
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