Hey guys, new to this forum and am getting ready to load some 6 creedmoor for a newly built remage. Components I have are alpha 6 creed lrp brass, sierra 107 smk's, and h4350. My main question is how much jump do the 107s typically like? Should I just go with hodgsdon's load data and seat them to 2.8? What do you guys find is the best method to determine the max coal in your rifle? Any suggestions would be great since this is my first time really messing with adjusting coal to a specific rifle. Thanks!
- Thread starter Mauser48
- Start date
You set the bullet in the case so it is just hitting the lands. Then measured the over all length to come up with 2.705?
Yes. I used the method where you take out the ejector and cocking piece and you keep seating the bullet a little deeper until there is no resistance on the closing or opening. The bolt would close at all until about 2.720. At 2.705 there was no resistance.
Check out this one. Better than the Hornady in that you don't need a modified case.
https://www.sinclairintl.com/reload...lair-bullet-seating-depth-tool-prod35491.aspx
https://www.sinclairintl.com/reload...lair-bullet-seating-depth-tool-prod35491.aspx
Use a comparator and compare your findings to SAAMI. Or call the smith that chambered it.
You are right, the method you used to find your lands is fine.
One thing, sometimes you can get a burr in the area you're working when the reamer stops going in. Can you see on your bullets a single mark or is there a ring all the way around a bullet. Seating a bullet 5 thou long and closing your bolt on it will divulge this. If a burr, firing 5 rds with a somewhat reduced load should iron it out.
If you have a 105 hybrid or a different shape bullet, see what you get for oal on one of those. The 107 does not have the most sleek ogive, and another bullets nose may just go into the rifling farther before contact.
Like mentioned above, I'd get ahold of the smith and find out if his reamer was bullet specific, or get the freebore dimensions of it, someone here can help with those numbers.
Thank you I'll try that as a bur in the chamber did cross my mind. All I have are the 107 smk's as this is my first time with a 6mm caliber rifle. The barrel is a criterion remage. I sent them an email to see if what I'm experiencing is normal for their chambers.
Heck, you may have a chamber reamed for a 110 Sierra, freebore is minimal with those bullets, and oal of your round is quite long.
I can tell you from experience, that .109" freebore is perfect for a 110 Sierra. Even running a sleeker ogive bullet like a 105 hybrid will result in the boatail junction being below the neck-shoulder junction in your brass.
You either need to ream your throat some, or switch bullets.
I've attached a file, if you look at your bullet and the 110, you should be able to visualize what is happening.
You either need to ream your throat some, or switch bullets.
I've attached a file, if you look at your bullet and the 110, you should be able to visualize what is happening.
If you are not planning on running Hornady bullets or a dtac, I'd steer clear of that match reamer, my .02
You most likely ordered a prefit, this is what I would do. Get a Hornady oal tool, a modified case, find a smith close with a throating reamer(unithroater), take your rifle, tools, caliper and comparator and set your freebore for your desired bullet.
I'm making the assumption you are new to custom chambers, as you go you'll learn reamer selection plays a big part in your success. With reamer info, guys or the smith can help decide what bullets will shine.
I'm making the assumption you are new to custom chambers, as you go you'll learn reamer selection plays a big part in your success. With reamer info, guys or the smith can help decide what bullets will shine.
Yeah that's the .183 freebore which would work better for your bullet of choice. It's what I use with the 108 ELD-Ms. I am at about .020" off the lands at about 2.795". Just need to figure the bullet you will use and get the right chamber set up.
Ok, I got the barrel back from criterion which they rechambered ro their 6mm match chamber. First let me say that criterion was excellent through the whole process and didn't charge me a dime which they didn't have to do. Now with the 107 smk, the bullet touches the lands at 2.796. This definitely sounds better to me. I'm thinking of seating to 2.775, this should now give me plenty of room for powder right? Within the cartridges limitations of course.
