Issue with 6x47 Lapua extraction

[accuracyman]

I have chambered three barrels on three different guns with the same 6x47L reamer and all three are having extraction issues (Clicks on extraction). I know right away everyone will say reduce your load. I have tried very light loads with the same result. It is a PTG reamer and it cuts a nice chamber but measures small. If you measure the extracted case after firing at the pressure ring .150-.200 above the head it measures the same as a new unfired case. To further add to the challenge a competition Redding die will not 'squeeze' or size the pressure ring at all. Obviously the chamber is too small for the Lapua brass that I am using so I am looking for opinions.

1. Polish the chamber to allow more clearance at the head of the case. (Seems like a lot to polish)
2. Get a small base die. (Seems pointless to try and reduce it smaller than new brass)
3. Get a new reamer ground that is larger in the body so these issues go away.

Obviously number 3 is the right choice but I am curious to hear what everyone thinks about polishing the chamber oversize. I am not new to chambering so this is not my first rodeo. I have chambered hundreds of barrels over the years but this is the first time I have run into a chamber that is too small for the brass.

How can I reach Dave Kiff directly so I can discuss getting a properly sized reamer? I know he has posted his direct email before but I am unable to find it.

I am curious to hear the different opinions I am about to receive.

Kris Whitman

 

[butchlambert]

Kris, Call me tomorrow. If you don't have my number I will PM it to you.

 

[Ggmac]

If you have them available , try remington 7br brass , it's .467 "
Is your reamer marked 6x47 Lapua ?
I know that's not the answer , just a possible quick solution .

 

[butchlambert]

If you have them available , try remington 7br brass , it's .467 "
Is your reamer marked 6x47 Lapua ?
I know that's not the answer , just a possible quick solution .

I believe the 7BR brass is too short to make the 6X47L.

 

[accuracyman]

Ggmac it is a new reamer and yes it is labeled lapua. The reamer print shows a pressure ring dimension .002 larger that the fired brass measures at the pressure ring. Thanks for the reply.

Kris

 

[Ggmac]

Da brain fart . Thanks Butch .
Yup time for a talk with Dave

 

[accuracyman]

Butch,

I was hoping you would jump in. I will ring you tomorrow after work. I am on my way to tennis tonight. Talk to you tomorrow.

Thanks,

Kris

 

[accuracyman]

I have received a few PM's from fellow members about my comment about the PTG reamer. To be clear this is not a slam on PTG or Dave Kiff. In fact most of my tools and reamers come from Mr. Kiff and I see no reason to change. I was just asking the knowledge base available to me thru this forum.

Please don't make this into a bashing thread because that is not my intent. I seek your experience and knowledge.

Thanks everyone.

Kris

 

[Riesel]

Kris, I've seen some of your barrel work at the Benchrest matches at Dietz. Problem is you make a barrel "too" perfect. Need to let that reamer
wobble a little.

 

[accuracyman]

I'll try that....hmmmm.....not exactly sure how to get that wobble but I'll work on it

 

[Roeder]

I have chambered three barrels on three different guns with the same 6x47L reamer and all three are having extraction issues (Clicks on extraction). I know right away everyone will say reduce your load. I have tried very light loads with the same result. It is a PTG reamer and it cuts a nice chamber but measures small. If you measure the extracted case after firing at the pressure ring .150-.200 above the head it measures the same as a new unfired case. To further add to the challenge a competition Redding die will not 'squeeze' or size the pressure ring at all. Obviously the chamber is too small for the Lapua brass that I am using so I am looking for opinions.

1. Polish the chamber to allow more clearance at the head of the case. (Seems like a lot to polish)
2. Get a small base die. (Seems pointless to try and reduce it smaller than new brass)
3. Get a new reamer ground that is larger in the body so these issues go away.

Obviously number 3 is the right choice but I am curious to hear what everyone thinks about polishing the chamber oversize. I am not new to chambering so this is not my first rodeo. I have chambered hundreds of barrels over the years but this is the first time I have run into a chamber that is too small for the brass.

How can I reach Dave Kiff directly so I can discuss getting a properly sized reamer? I know he has posted his direct email before but I am unable to find it.

I am curious to hear the different opinions I am about to receive.

Kris Whitman

The new reamer ground to the correct size is the permanent solution, but option 1, polishing the chamber to enlarge it slightly will certainly work and at least allow you to get shooting while you wait for a new reamer. It is not that big of a deal to polish .001 to .002. It is a skill set that you really should have. Done carefully and correctly it will not harm your meticulous reaming job in any way. Hand work is so much a lost art these days.

 

[butchlambert]

Kris, My reamer print shows .472 @ .151 from the bolt face and .4578 @ 1.400 above the bolt face. I agree with Scott on this. My new brass measures approx .4689 and at the shoulder .4532.
My once fired brass measures .4708 and ..4599.
I measured my once fired brass twice and 4 pieces of it. The .4599 seems suspect.

 

[accuracyman]

Well I have my fix. I cut off the old shank and machined a new shank and threads. Ran a new 6XC reamer in this barrel and problem solved. Shoots better than it ever did as a 6x47 lapua without having to neck down 6.5 brass. The Norma 6XC brass is excellent without any headaches. I am done with the 6x47 lapua! Just wanted to follow up since many offered advice.

Thanks,
Kris

 

[butchlambert]

Well I have my fix. I cut off the old shank and machined a new shank and threads. Ran a new 6XC reamer in this barrel and problem solved. Shoots better than it ever did as a 6x47 lapua without having to neck down 6.5 brass. The Norma 6XC brass is excellent without any headaches. I am done with the 6x47 lapua! Just wanted to follow up since many offered advice.

Thanks,
Kris

You did good Kris.