Need help choosing 6.5 Creedmoor chamber dimensions.

[68bthp]

I need to order a reamer. I'm going to be handloading exclusively for a 6.5 Creedmoor custom bolt action rifle. I want to shoot 130 or 140 Berger or 130-140 Hornady bullets out of Hornady cases but I don't want to turn brass. Whichever bullet will group 1/4" to 3/8" 5 shot groups at 100 yards will be the chosen bullet.

I'd appreciate it if you Creedmoor guys who have been successful at shooting sub 1/2" groups could tell me what chamber dimensions you are using. In particular, are you using .20" freebore? I will be using an AICS magazine, but the 2.820" OAL shouldn't be a problem. What is the chamber neck diameter? Right now my Hornady cases with a Berger 140 bullet seated in them is .290 diameter, and so I was wondering if a .294 neck is in order? ...etc. Thanks.

 

[Rob01]

Get the standard Creedmoor reamer. It's all you need.

 

[JGorski]

If it were me Id go with a 292 neck, but thats just me. I ordered a new reamer for my 2nd 6 Creedmoor and asked Dave to make it a 274 neck, my current 6 Creed is 275 neck, we'll see which one shoots better if at all.

 

[STR]

Get the standard Creedmoor reamer. It's all you need.

I agree 110%.

 

[68bthp]

What I find a little bit unsettling (from a precision handloaders standpoint) , is that while a 140 berger bullet seated in a Hornady case is .290", the SAAMI is listed as.296. Having 6 thou space at the neck seems a bit excessive to me, and should be closer to 4,000ths with a .294 neck. Otherwise, I'm inclined to agree that all the other standard SAAMI dimensions seem to work well.

JGorski,
I would first want somebody to tell me that they have good experience with a very tight neck with about 2,000ths clearance on the 6.5 creedmoor before ordering the reamer that way. The reason I'd be leary about such a snug neck with no feedback from 6.5 Shooters is because of the known anomoly with the 284 cal. For some reason, the 284 does NOT fire as accurate with less then 4,000ths clearance.(...or maybe 3,000ths at minimum). I'd not want to find out the hard way that the 6.5 Creedmoor might have this same peculiarity.

 

[Rob01]

I have been shooting the standard chamber with factory ammo for 5 years and I can tell you it's very accurate. If the smith does his job right the standard chamber will be more accurate than you will be.

 

[Edds]

... In particular, are you using .20" freebore? I will be using an AICS magazine, but the 2.820" OAL shouldn't be a problem....

A 140 gr Berger will be about .040" away from the lands with .200" freebore and a 2.820 OAL.

 

[bward]

Whatever you decide, don't go with a .292 neck. 2 thousandths neck clearance isn't nearly enough. The first spec of carbon or anything else in the neck area will make the chamber too tight, which will kill accuracy and possibly make your rounds not chamber. A .294 or .295 neck would be appropriate for a .290 loaded diameter.

As far as freebore goes, I think the standard is a .194. I'm going from memory, but I believe that's close. I wouldn't go any longer than that. That reamer has worked really well in a lot of rifles.

 

[68bthp]

As far as freebore goes, I think the standard is a .194. I'm going from memory, but I believe that's close. I wouldn't go any longer than that. That reamer has worked really well in a lot of rifles.

I called Hornady Thursday and they confirmed it's .200 freebore. Dave at PT&G uses .199 freebore. (I guess the silly little .001 difference is to avoid patent infringement)
I already spoke to Dave, and he was all over the map with reamer freebore choices, offering me .156, .173, and .199 freebore. He kind of was just leaving the decision to me but I don't know enough about it. (that's why I'm now HERE) He scared me by saying that guys using the 140 grain bullets with less then .200 freebore (or .199) were experiencing pressure problems and flat primers. That was enough for me to just order a standard reamer. I have 4-6 weeks before Dave makes it and sends it to me. If I change nothing else, I think I'll call Dave and have him at least bring the reamer case neck diameter down a thou or two from .296 to .294-.295 (maybe I need to order another bag of Hornady brass just to double check on the neck diameter variances from lot to lot)

 

[6brshooter]

I have 4 different creedmoor barrels, all savage prefits. One factory lrp, a criterion, a shilen select match, and a brux, everyone had the same oal chamber with 140 amax, they all shoot3/8" or better. Well the factory lrp is more like mid .4s. In other words the standard reamer is my choice , no need of dicking around with what works. Get a no turn neck reamer and then brass changes nk dimensions and u got to turn nks, no good. Been down that road a couple times with 6 br lapua brass.

 

[68bthp]

A 140 gr Berger will be about .040" away from the lands with .200" freebore and a 2.820 OAL.

I hope you're on the money with that. It will make me feel better tom know that a 140 grain bullet will sit that much close to the lands and NOT a looooong .200" away from the lands. Until you said this, I had wondered why Hornady and Creedmoor Sports designed the 140 grain cartridge to seat .200" far away from the lands. Now I'm wondering if it's more like the 130 grain factory cartridges will seat .200" away from the lands, and the longer 140 cartridge seats closer, like at the .04" you mention.

 

[Edds]

If all you want is a finish reamer, Grizzly has a PTG standard SAAMI reamer in stock.

Some people like the Berger VLD bullets to touch the lands.

 

[68bthp]

I have 4 different creedmoor barrels, all savage prefits. One factory lrp, a criterion, a shilen select match, and a brux, everyone had the same oal chamber with 140 amax, they all shoot3/8" or better. Well the factory lrp is more like mid .4s. In other words the standard reamer is my choice , no need of dicking around with what works. Get a no turn neck reamer and then brass changes nk dimensions and u got to turn nks, no good. Been down that road a couple times with 6 br lapua brass.

Oops, I was busy posting at the ame time you were.

Thanks for that info. But I probably will have to do something "custom" just to feel better, and I will order the reamer at least 1 thou tighter at .295. LOL
BTW, pardon my ignorance; what is "lrp" you mention. Also, have you had any luck with fine accuracy using 130 grain bullets in your same chambers that has worked with the 140 grain bullets?

 

[6brshooter]

Savage model 12 Lrp, just a factory rifle. Target action with a large shank barrel.

 

[bward]

I called Hornady Thursday and they confirmed it's .200 freebore. Dave at PT&G uses .199 freebore. (I guess the silly little .001 difference is to avoid patent infringement)
I already spoke to Dave, and he was all over the map with reamer freebore choices, offering me .156, .173, and .199 freebore. He kind of was just leaving the decision to me but I don't know enough about it. (that's why I'm now HERE) He scared me by saying that guys using the 140 grain bullets with less then .200 freebore (or .199) were experiencing pressure problems and flat primers. That was enough for me to just order a standard reamer. I have 4-6 weeks before Dave makes it and sends it to me. If I change nothing else, I think I'll call Dave and have him at least bring the reamer case neck diameter down a thou or two from .296 to .294-.295 (maybe I need to order another bag of Hornady brass just to double check on the neck diameter variances from lot to lot)

Yes that is correct. .199 is the reamer most barrels I know of have been chambered with. I knew it was right around there. I spec'd mine with a .184 freebore as I plan on using it mostly with 130's and did not want to run out of neck when chasing the lands.

 

[JB02]

I agree 110%.

[MENTION=55312]68bthp[/MENTION], if a top shooter and a well known gunbuilder are telling you the same thing, you should listen. Don't waste your money on a custom reamer.

 

[68bthp]

[MENTION=55312]68bthp[/MENTION], if a top shooter and a well known gunbuilder are telling you the same thing, you should listen. Don't waste your money on a custom reamer.

Pardon my ignorance. If you look at my post count, you'll excuse me for not being familiar with the folks on these forums and didn't mean to be dis-ing anybody here.....if that's what I was perceived to be doing.
On the contrary, the reamer I've already ordered from Dave (and I'm double checking here with you guys) is quite the standrad 6.5 reamer with .199 freebore and a 1 °30 lead angle, at quite the usual price of $139.

However, there are still discrepencies or differences that are no fault or choice of my own; for example Hornady is telling me their SAAMI throat is .2645, while Dave's reamer is .269 I will need to call Dave back and sort these differences out and choose one.