How do you measure barrel length

[Tahoe Shark]

i was playing with Quickload and OBT times when it occurred to me that I may be using the wrong figure for barrel length. I have always used the total length of the barrel including threads. That seems to make sense to me and all of the 30" finished barrels I have ordered are 29" from the action to the end of the barrel. I am just not sure how much the barrel " vibrates" inside the action and maybe I am using the wrong measurement.

Which is correct?

 

[DRNewcomb]

Legally, in the US barrel length is measured by inserting a rod down the barrel until it contacts the bolt face, breach block or whatever. Not sure how Quickload does it.

 

[Phil]

I usually state from the recoil lug or action face, but if you really want to go wild you can subtract the chamber and freebore as well. .....

 

[BLCKWLF]

Legally speaking... An excerpt from ATF FAQ on Title 2 firearms:

"The ATF procedure for measuring barrel length is to measure from the closed bolt (or breech-face) to the furthermost end of the barrel or permanently attached muzzle device. Permanent methods of attachment include full-fusion gas or electric steel-seam welding, high-temperature (1100°F) silver soldering, or blind pinning with the pin head welded over. Barrels are measured by inserting a dowel rod into the barrel until the rod stops against the bolt or breech-face. The rod is then marked at the furthermost end of the barrel or permanently attached muzzle device, withdrawn from the barrel, and measured. "

 

[Tahoe Shark]

Thanks, but

My question is not for the legal definition of barrel length. It is in regards to Quickload and OBT calculations for barrel timing

 

[BCBRAD]

I've done it by the method described above for the Quickload program and to get a barrel time that coincides with a node.
It seems to work OK doing it this way as I can get a very good load 99% of the time.

 

[Mozella]

Thanks, but

My question is not for the legal definition of barrel length. It is in regards to Quickload and OBT calculations for barrel timing

I'm almost sure Quickload tells all about how to measure barrel length in their rather lengthy set of instructions. Now I could be wrong, but I could swear I read it there. I do know that I measured all my barrels when I first got Quickload using a rod down the barrel method and I can't imagine just making up the procedure. I could root back through the instructions to be sure, but I'll leave it up you to prove me right or wrong. If I'm wrong, I'll offer an apology.

 

[stgw77]

Talked with Dan, "inventor" of OCW theory, and he said he measures BBL length from bolt face to muzzle end (so, threads are included). You can also read this on his website. Hope it helps.

 

[Tahoe Shark]

Talked with Dan, "inventor" of OCW theory, and he said he measures BBL length from bolt face to muzzle end (so, threads are included). You can also read this on his website. Hope it helps.

Thanks

 

[Brians356]

The value the OCW theorist used may or may not be what QL uses. Or is Dan "inventor" of OCW theory also the creator of QuickLoad?

 

[Dusty Stevens]

What if dan had a 1.75" cartridge and a 2.25" ctg with .250 freebore- how does he measure the barrel on that?

 

[Cakes]

Dusty-
You've chambered just a "few" barrels. When a customer wants a "30" finished", do you use the muzzle to bolt face? I might have been confusing myself all these years. Eric in DL

 

[Dusty Stevens]

General gunsmithing concensus is total length crown to end of threads. This in no way correlates to the length of the rifling nor the length from the boltface. If you want a barrel 30" your gunsmith is gonna make it 30" total overall length

 

[therifler]

that's the way i do it . but interesting facts about measuring from the bolt face on ATF requirements. gives you about an extra 1/8". just a guess about QL's i would say down the barrel with the rod.

 

[butchlambert]

From the boltface.

 

[rardoin]

Input the boltface to muzzle crown length and QL will produce an estimated effective barrel length based upon SAAMI specs for the cartridge. Unusually short or long freebore may affect the software calculated effective barrel length but I am not sure how much this will affect the results obtained.

 

[ebb]

Like you measure a cats tail.