Home Forums Hunting & Shooting Ask The Gunwriters 6.5 Creedmoor - Reloading 101 goes out the window!

I bought my custom 6.5 CM PRS rig precisely because I didnt want to have to reload for it but still wanted it to shoot great. And it does mine shoot sub 1/2" 5 shot groups with the cheaper 6.5 Gunner ammo by Hornady rather than the more expensive Match 140ELDM's. No complaints there. Thats the magic of the Creedmoor not only the cartridge was designed but it was a whole ecosystem, the SAAMI chamber the factory ammo - it was all good from inception!

Now the reloader in me could not bear to see all that empty brass! Brass prepped then on the measure distance to lands with the Hornady OAL guage. Oh oh - That's when problems started. The measurement I got with the 140gr ELDM bullet was some 90 thou shorter than loaded factory rounds with the same bullet. I even tried rotating the tool and pushing the rod in harder. Still shows a large discrepancy. Then I coloured an factory round with texta and loaded it. Wow hard to extract! (Took firing pin out first). Nearly all of the texta colouring was removed around circumference of the bullet.

Must be a custom chamber right - No it was stock SAAMI chamber. Then I found out that SAAMI spec throat is .2645" and throat length is .199". Verified with the gunsmith.

Obviously millions of 6.5CM rounds have been fired so its not a safety issue but how do I determine seating depth now??? I am no engineer but I don't think the Hornady tool has a hope of working if the throat is only 1/2 of a thousands of an inch over bullet diameter - bullet was right on at .264". For all intents that is full contact.

How do you overcome this issue in reloading? Is this the new norm in cartridge design ? Long freebore tight throats.

Just check your throat length one of the old timey ways.
Easiest: Take a fired case. Pinch the neck with your fingers just enough that it will hold a bullet. Take the bullet and color it all the way around with a sharpie. Just barely push the colored bullet into the pinched case. Chamber and close the bolt, pushing the bullet into the case when it contacts the lands. Extract - if the bullet comes out with the case, just measure. If it doesn't, but stays in the lands, tap it out with a cleaning rod and then push it back into the case to the point where the sharpie mark was scraped off by being pushed into the case when you chambered it. Measure and you're done.

Good luck. You definitely have a problem I'd like to have...LOL
Rex

If the marks on your bullet run around the full circumference of the bullet, instead of just marks from the lands, you might have a carbon ring building.

John

I'm no rocket scientist, but I've found one can determine what works best by pulling the trigger.

You say the gunner ammo works well, seat your bullet so the ogive is the same distance from the case mouth as the gunner ammo.

How many rounds down the barrel and do you clean it? Hondo may be on to something. Other than that, I'd suggest learning how to check where your lands are the old fashioned way, as TREX suggested. No need for the Hornady tool. A lot of you guys need to learn about going back to the basics and simplifying the reloading process. You shoot a "custom PRS" rig, you should know a little more about this schidt.

Do you still have a prostate, or were you born a raging ahole?

Do you have a carbon ring in the throat?

You should really STFU when the adults are talking.

I clean after each range session (20-30 rounds)and use Mpro 7 with a bronze brush. Confident its not a carbon ring.

And yes when I put a factory round in it takes the texta marking off all around the bullet. Although with only 1/2 thousadn's inch clearance in the throat I dont think you can push the bullet to the lands. It's gets stuck in the throat already.

The paper tiger rides again.
Outsert the stick already dude.

There's always the chamber cast approach, if you're really good with a caliper. That will also tell you if you've got some under-minimum throat that is causing some issues. As a bonus, such a tight throat means you don't really have to worry about where the lands are, and chances are seating off them a ways will IMPROVE accuracy. If you prefer a looser throat dimension, fire-lapping will get that done, but it can be overdone if you aren't careful.