New to reloading with a question on 6.5 Creedmoor.

[tinnmann94]

I started reloading and I'm trying to find the lands on my rifle. I have been shooting factory 140 grain eld match and have had luck. The rifle is a Bergara ridge back Premier. The factory ammo has a o.c.l of 2.800 and Measurements I'm coming up with is 2.595 to 2.610 to the lands on my rifle . This seems really short to me. Thoughts ? I also have Measured this three different ways. Maybe I'm over thinking this cause I'm new to this.

 

[QuietTexan]

Break it down for us, exactly what you're doing. There's probably one step in the process that's throwing you for a loop. Could just be comparing apples and oranges, or one detail you're missing. Even if you are overthinking it that's ok, that's how I live my life. We'll get you there

1. What tool are you using to measure distance the lands with?
   1. Are you pushing hard enough to get a hard stop and marks on the bullet?
2. What are you measuring BTO with?
   1. What is the BTO if a factory round with OAL of 2.800"?
3. What are you measuring and what with when you're getting 2.595-2.610? Is this COL or BTO?

COL or COAL - Cartridge Overall Length - primer to bullet tip
BTO - Base to ogive - Primer to ~one caliber diameter on the bullet

 

[tinnmann94]

I used 3 ways to check this. First I used the Hornady lands tool and the the old fashioned way with breaking down the bolt and making a dummy round till the bolt drops freely and finally marking a bullet with marker to see where the lands is. They were all pretty close. The measurement is over all cartridge length. The bto of the factory round is 2.177. And I believe I'm pushing hard enough with the tool.

 

[The Oregonian]

Using the Hornady tool I have had some trouble getting repeatable measurements, mainly bc it is hard to replicate the pressure on the bullet when pushing it out of the case in the chamber.

I would trust the disassembled bolt or a sharpie on the ogive method more than the Hornady. If it were me I would back 20 thou off the average of a few different methods and start with that as my longest CBTO and work from there.

On the factory COAL, it seems like .2 inches would make it difficult to close the bolt on your rifle with those dimensions. What is the CBTO of the factory round? I think you are quoting your cartridge as CBTO and the factory round as cartridge overall length.

 

[beaueel]

Have you looked at Hornady's Comparator system. They will make you a custom case out of one of you fired rounds. Then you can check head space, as well as many other specs. Look into it. I really enjoy mine.

 

[tinnmann94]

Have you looked at Hornady's Comparator system. They will make you a custom case out of one of you fired rounds. Then you can check head space, as well as many other specs. Look into it. I really enjoy mine.

I do have that and I believe it works well. My question is mainly about the chamber length and the possible short chamber.

 

[QuietTexan]

My question is mainly about the chamber length and the possible short chamber.

Doubtful if you don't have to cam the bolt down hard on the factory ammo. I sat a batch to 2.900" COL once the bolt wouldn't close. You're talking the factory ammo being double to triple that far off compared to your reading.

You're using a 140 ELD-M to measure distance to lands with?

 

[The Oregonian]

Two measurements that would help us…what is the COAL of your round and factory? And what is the CBTO of each, using the same tool to measure each one?