AR 15 questions again!

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newmexkid

New member
Time to start working on the new AR again. When reloading, how do you find the COAL of your particular AR? Or does a person just follow book guides?
 
When starting out I would just load to book length. One way to find where the bullet hits the lands is drop a loaded cartridge or dummy round in the chamber and hold it in with a rod of sorts and then run a cleaning rod in the muzzle until it touches. Put a piece of tape very carefully on the cleaning rod so it just touches the muzzle. Knock the round out then drop a bullet in and hold it in the chamber with the rod and then reinsert the cleaning rod into the muzzle until it hits the bullet. Measure how far the tape is from the muzzle. This measurement is how far the bullet in your loaded round is from the lands when chambered. Once you get the seating dept figured out the best way is to load by measuring at the ogive . I use the Hornady bullet comparator kit. bullet tip lengths will vary quite a bit from lot to lot.
 
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Originally Posted By: TnTnTnI load so that the coal clears the front of the magazine body by a few thousandths... I like repeaters...


Works for me as well.
 
I use the Sinclair tool for measuring distance to lands. Fast, accurate and repeatable. It is far easier to use than the Hornady tool that I also have used and you aren't hobbled buying or making the converted cases.

Greg
 
Originally Posted By: GLShooterI use the Sinclair tool for measuring distance to lands. Fast, accurate and repeatable. It is far easier to use than the Hornady tool that I also have used and you aren't hobbled buying or making the converted cases.

Greg

How does this Sinclair tool work? Is it caliber based? Could this be used for a wildcat round?

Also how important or how beneficial is it to know your distance to the lands? Thanks
 
Originally Posted By: HcboyOriginally Posted By: GLShooterI use the Sinclair tool for measuring distance to lands. Fast, accurate and repeatable. It is far easier to use than the Hornady tool that I also have used and you aren't hobbled buying or making the converted cases.

Greg

How does this Sinclair tool work? Is it caliber based? Could this be used for a wildcat round?

Also how important or how beneficial is it to know your distance to the lands? Thanks

The Sinclair uses a FIRED case from YOUR chamber. To make them work slick you size the case down enough to take some of the body expansion out but NOT move the shoulder. No taping etc. First step is drop a bullet in the chamber and get the distance from the action insert to that base. Then you drop the case, after removing the bullet, in the chamber and get a measurement from the rod to the back of the action insert. The rod has stops that have a collar on them. Measure the collar distance add the bullet LENGTH and you have COL for distance to lands. Sinclair/Brownells has a good little video on it's use.

It is made to order for a wildcat as you aren't sending in cases to get tapped ,unless you do them yourself, and ittakes much less finesse in checking the bullet location in the lands. Keep that case for a reference and you will always be ready to measure that chamber. Very nice as you are able to adapt to slight vagaries of chambering. No generic to mess with a sit is rifle specific.

It is extremely important in many chambers to knwo where the lands are if you are dealing with accuracy work. In a wildcat it is imperative as you have no standardized load length unless you determine it yourself. You can' say it's an AR so therefore I can load to 2.260 or XXX. In reality like our 6X6.8 you set the bullet to the chamber. My new 6X6.8 for instance has a 87 VMAX at 2.282 but 87 Varmint BTHP is at 2.251. In the American 30 my MAX col for a 150 Sierra SP was 2.295 but a 110 RN was at 2.008.

Some bullets need different seatings going in. The VLD likes to be uptight on the lands while others like the Barnes need about 0.050 off.(per them)

So yes it is VERY important if dealing with non-SAAMI chambers and even if you are seating in and out is a major step in tuning on several levels. I can assure you that loading every 69 grain SMK in every 223 SAAMI chamber to 2.260 will not get the best performance out of every barrel. Plus remember every time you fire that rifle the throat is altered. Not much but every 500 rounds or so it would behoove one to check the lands distance and maybe move the bullet out a bit more if you can to chase the lands and if you can't maybe change bullets to get the distance you work at back.

Greg
 
I disassemble my bolt, sometimes pull the barrel, then do a bolt close test. That gives me my base to shoulder length then my base to ogive length.
 
Originally Posted By: TnTnTnI load so that the coal clears the front of the magazine body by a few thousandths... I like repeaters...

I do this. I ignore the cannelure if it has one and load as long as possible to fit the magazine.

kwg
 
Originally Posted By: old catOriginally Posted By: TnTnTnI load so that the coal clears the front of the magazine body by a few thousandths... I like repeaters...


Works for me as well. Ditto x3
 
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