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Help me spec a 6BR reamer

I have helped so many people you would not believe. All advise was helpful. I just hardly ever try here for obvious reasons. Good luck in your quest.

I'm sure that's the case, but doesn't seem so in this particular thread. I cant answer as to why, you are the one that is choosing to pick apart my wording rather than answer the question I asked. I'm not looking to spend all day on the internet battling over words.
 
I have been in your shoes, trying to learn, but am more than humble to ones offering help. I have said "Thank You" many many times to shooters who have helped me.
 
I have been in your shoes, trying to learn, but am more than humble to ones offering help. I have said "Thank You" many many times to shooters who have helped me.


I’m not going to thank you for choosing to patronize me rather than helping. If you’re looking for pats on the back, try another approach.
 
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Patruck825, is there a bullet that you have in mind to shoot? I see you asked about the 110 SMK in another thread.

If you do have a bullet in mind, except for that 110 since no one answered, you might do some searching. Since this is a popular round, I am sure a bullet/freebore measurement has been tried and tested.
 
Patruck825, is there a bullet that you have in mind to shoot? I see you asked about the 110 SMK in another thread.

If you do have a bullet in mind, except for that 110 since no one answered, you might do some searching. Since this is a popular round, I am sure a bullet/freebore measurement has been tried and tested.

I’ll be shooting solely the 105 hybrid, that’s what I’m currently shooting as mentioned in the first post.

I’ve looked it up and that’s what led me to the confusion over freebore, everyone seems to reccomend something different
 
Sorry, got caught up in the other nonsense and overlooked that in the first post.

And, you're right. Looking around, there are a lot of varying thoughts to the better freebore.

The advantage of a longer one is you can seat the bullet further out of the case to keep from touching the donut area. How far into the neck are you now with your loaded rounds and your .094" freebore? How many rounds down the tube and how far has your lands moved?
 
Sorry, got caught up in the other nonsense and overlooked that in the first post.

And, you're right. Looking around, there are a lot of varying thoughts to the better freebore.

The advantage of a longer one is you can seat the bullet further out of the case to keep from touching the donut area. How far into the neck are you now with your loaded rounds and your .094" freebore? How many rounds down the tube and how far has your lands moved?

Apologies for all that nonsense.

So here is where I am at with seating, 15 thou off the lands.

As far as erosion, my measurement now at 912 rounds is the same as it was when it was new. Same Bullet, same tool, same case. I don’t know if it’s possible to have experienced no erosion, but it is at most minimal.

D2CF9857-B38C-4E6D-B6BA-8C0E1F648311.jpeg
 
Looks good to me, but I am sure someone with a lot more experience will chime in.

If you haven't had to start chasing the lands, then a small step up won't hurt a thing and give you that extra bit of room. Other than the tight necks, anything else you really don't like about the reamer you are using now?
 
Looks good to me, but I am sure someone with a lot more experience will chime in.

If you haven't had to start chasing the lands, then a small step up won't hurt a thing and give you that extra bit of room. Other than the tight necks, anything else you really don't like about the reamer you are using now?

Not really, the tight neck is really the only thing that I’ve had an issue with and the only thing I set out to fix with this next reamer. The rest of it was really kind of a “while I’m at it” thing. I will likely up the freebore to .104 or .114, neck to .272, and feeebore diameter to .244 per Alex wheelers reccomendation.
 
This is my current reamer, correct me if I’m not reading this correctly but does this show my FB at .107?

View attachment 1062257
This will suit your needs, a Harrell’s #3 will size the .200” line and shoulder enough, personally I would change the neck from .271” to .272” and I changed the freebore diameter to .244” on my own reamer for a little more clearance. The .094” fb will work well..
 
This will suit your needs, a Harrell’s #3 will size the .200” line and shoulder enough, personally I would change the neck from .271” to .272” and I changed the freebore diameter to .244” on my own reamer for a little more clearance. The .094” fb will work well..

Harrell’s gave me what it looks like is stamped a B1 die for this brass. I am definitely going to change to a .272 neck, may even ask for .2725 as a Bullet Still doesn’t drop free into cases I’ve turned a thou off of.
 
Harrell’s gave me what it looks like is stamped a B1 die for this brass. I am definitely going to change to a .272 neck, may even ask for .2725 as a Bullet Still doesn’t drop free into cases I’ve turned a thou off of.
My B3 sizes around .001” or less at .200” line and shoulder, don’t know what the B1 would size I’ve never used one.
 
The current 6BR reamer they have has a .271 neck and id like at least a .272 or .273 neck. My Current barrel is a little tight with lapua blue box.
You can do as you wish but I started shooting a 6mm BR 15 years ago and my first reamer (and the largest neck diameter) was 0.271". It was never "tight" even through several cases of unturned gold box brass. I've never even heard mention of a 0.273" or 0.274" neck diameter.
the 105 hybrids typically measure .2434-.2436 at the p ring
If you buy Berger 105 Hybrids that measure 0.2435" or larger call them right away as they never should have gotten out of the factory. Standard/typical chamber freebore diameter for 6BR is 0.2435" and you sure don't want bullets that fat. The 105 Hybrids made with the original die started at 0.2426" and over time got up to 0.2435" as the die wore. I had a 2,000 count lot in that diameter which would not shoot and Eric gladly replaced then.
My loaded rounds measure out to .2695, so id be looking at a .273 - .274 neck. I had some pressure issues early on and i think it had to do with the neck, a bullet doesnt drop freely (only barely) into a fired case.
I don't know where your pressure issues came from but it wasn't chamber neck diameter. All a 0.273-0.274" neck diameter will get you is short brass life.
Ive seen Freebore recommendations of .104, .114, .120, and .140. Whats the advantage of going with one over the other?
It depends on the bullet. I have a 6mmBR reamer with 0.195" freebore that was ground to shoot Randy Robinette's "Bob-tail" bullets. Very long bearing surface and real short boattail. That's what it took so that's what I had made.For what you want to do anything other than 0.110" - 0.115" freebore is a waste of time. 105 Hybrids work well and so do 87 VMax.
Question for you guys, can you use this reamer print to determine your Base to Ogive length? Looking at the reamer print, none of the measurements i would think to use seem to line up with the measurements ive pulled using the stoney point gauge, i get a BTO length of 1.7930
No two Stoney Point/Hornady tools have the exact same diameter hole. The results are reproducible but a meaningless number. I have three 6mm inserts and the results vary by over 0.035".
Since you are looking at a new reamer, get one with "0" free bore and allow your gunsmith to cut the throat separately, so you can get exactly the free bore length you want. This will allow your gunsmith to be able to cut many more chambers with this particular reamer, and then he can cut any throat length that other customers may desire.
With all due respect, that's just plain dumb.

The idea of making the freebore diameter larger than 0.2435" is good but not sure I'd go to quite to 0.244".

I would never leave my reamer with a gunsmith. It's not like they take up a lot of space. They get "lost". One got "re-ground". One got used a whole lot of times I didn't find out about until much later.

A standard 6BR Norma reamer with 0.114" freebore, 0.272" neck diameter will do anything you want it too. Off the shelf at Grizzly.
 
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Freebore diameter should be .2430 -.0000 +.0003

Why would anyone ever go larger than .2430 freebore diameter? Going larger is comparable to already having a couple thousand rounds shot through the barrel!

Freebore length is always cut to match your specific bullet and preferred seating depth.

Many guns that shoot in the 1's or less can't be wrong!
 
Why would anyone ever go larger than .2430 freebore diameter?
Because some bullets are larger than 0.2430" in diameter and you do not want the freebore swaging the bullet. If nothing else it's not good for accuracy.

Going larger is comparable to already having a couple thousand rounds shot through the barrel!
There should be no contact between the bullet and the freebore. Freebore length and diameter should be the same at 10,000 rounds as when it was new. The throat may be worn away but that's not freebore.
 
Copy of 6mmBR -2.271 neck .040 FB.jpg

Here is a reamer drawing of what I have used for several bbls. with excellent results ,,,(this is my short range reamer,,my long range reamer has .120" FB),,,it works with the old gold box brass as well as new blue box Lapua brass,,,,Roger
 
You can do as you wish but I started shooting a 6mm BR 15 years ago and my first reamer (and the largest neck diameter) was 0.271". It was never "tight" even through several cases of unturned gold box brass. I've never even heard mention of a 0.273" or 0.274" neck diameter.

If you buy Berger 105 Hybrids that measure 0.2435" or larger call them right away as they never should have gotten out of the factory. Standard/typical chamber freebore diameter for 6BR is 0.2435" and you sure don't want bullets that fat. The 105 Hybrids made with the original die started at 0.2426" and over time got up to 0.2435" as the die wore. I had a 2,000 count lot in that diameter which would not shoot and Eric gladly replaced then.

I don't know where your pressure issues came from but it wasn't chamber neck diameter. All a 0.273-0.274" neck diameter will get you is short brass life.

It depends on the bullet. I have a 6mmBR reamer with 0.195" freebore that was ground to shoot Randy Robinette's "Bob-tail" bullets. Very long bearing surface and real short boattail. That's what it took so that's what I had made.For what you want to do anything other than 0.110" - 0.115" freebore is a waste of time. 105 Hybrids work well and so do 87 VMax.

No two Stoney Point/Hornady tools have the exact same diameter hole. The results are reproducible but a meaningless number. I have three 6mm inserts and the results vary by over 0.035".

With all due respect, that's just plain dumb.

The idea of making the freebore diameter larger than 0.2435" is good but not sure I'd go to quite to 0.244".

I would never leave my reamer with a gunsmith. It's not like they take up a lot of space. They get "lost". One got "re-ground". One got used a whole lot of times I didn't find out about until much later.

A standard 6BR Norma reamer with 0.114" freebore, 0.272" neck diameter will do anything you want it too. Off the shelf at Grizzly.

Ill reply to your posts in order...

- if my neck inst tight, why wouldn't a bullet drop freely into a fired case?

- i have 3 lots of berger hybrids currently and they all measure from .2434-.2436, from other experiences ive heard this is common

- I always have to wonder why folks think an extra .001 of expansion in the neck is going to shorten brass life when a lot of folks are out here blowing 6BR cases into dasher without brass life issues. I am not in the camp of thinking that expanding my brass an extra .001 is going to have a meaningful impact on brass life.

-.244 freebore diameter is what was recommended to me by alex wheeler, i am not convinced .0001 in either direction makes all that big a difference.

- I agree, i don't plan on having a reamer spec'd to 0 freebore for other customers. If i have to pay for a reamer to get the specs i want, they can too. My reamer will be cutting my barrels and returning home when its done.
 
I could explain each of these to you but based on your responses to me and everyone else who has tried to help you it would obviously be a waste of my time. Despite starting off with "I dont know much about reamers or what aspects are important to specify so any guidance would be appreciated" you've decided you know more than those of us who have been shooting that specific cartridge chambered with a number of different reamers for many years.

Good luck to you. I hope your magic reamer is everything you envision and may all of your 105 Hybrids fall free into the neck of a fired case since that seems to be something you've decided is important. And may all your future barrels show no throat wear after 900 plus rounds.

Now where's that ignore button.....
 
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