Stamped neck size?

G

Greyfox

Active member
This is something I thought I knew, but apparently not. I am helping a friend who hasn't shot in nearly 30 years get started up again. He has a rifle that was smithed by Fred Sinclair. It's a Remington 40X in 6PPC and has 6PPC/262 neck stamped on the barrel. The fellow has brass that was given him by Sinclair and shot in the rifle. it measures .010 thick. A loaded round, of course, measures nearly .264 and chambers easily. My question is, does the # stamped on the barrel typically mean the size of the loaded round or the actual neck size of the chamber? The barrels I have with neck sizes stamped have always been the actual neck size, but I'm wondering if that wasn't the case 30 years ago or am I just missing something. I am intending to do a chamber cast, but haven't had the time yet.

Rick
 
The size stamped on the barrel is normally the chamber neck diameter but who knows what happened from Sinclairs till today.

You could contact Sinclairs to see if they still have records on this gun, but, Sinclairs is now owned by Brownells and much of the Indiana operation is
being relocated to Iowa so records of old builds may be hard to locate at this time.
 
Thanks Jerry,
That's what I thought. However, several years ago I had "world famous Savage Guru" Fred Moreo, rechamber a barrel for me. I specified that it be a .265 neck (6-250 chamber). The barrel arrived (two months after the promised date) with .265 NK stamped on the end of the barrel. I had (like an idiot) made prairie dog brass in advance and when chambered it didn't feel quite right. I poured a chamber cast and it turned out to be a .269 neck. Whe I was finally able to reach Mr Moreo (after calling two weeks) he pretty much told me that was tough $h!t, but he just went by what the reamer said and blamed Dave Kiff. Makes me wonder about neck sizes, gunsmiths and such.....

Thanks for your input,
Rick
 
If you want to know the chamber neck diameter you have to measure it - it's that simple. Gunsmiths and reamer makers have bad days just like everybody else. Often, the fired case neck diameter will be a thou smaller than the actual chamber diameter.
 
Rick,

This 262 neck doesn't sound right with the .010 brass thickness. I have turned some brass at .009 and didn't have to neck size as the brass would hold the bullitt. The brass being that thick you should't have to neck size. Is this true for you? Later, charlie
 
One other possibility is that the neck was opened up at a later time. 30 years is a long time especially if the rifle has ever changed hands. Not uncommon for a tight necked chamber to be opened up to a larger neck diameter later on especially if someone gets tired of turning necks. The best way of checking neck diameters on the chamber is with pin gages. I have a set of Deltronic pins in both 6mm and .22 that are in .0005" size increments. I think the 6mm size starts at .2615" or .262" and goes up from there. I haven't ever had a reamer cut smaller than what it was marked, but I guess wear on the neck could cause it to cut smaller. It would be pretty hard to get a .262" necked reamer to cut a chamber that was as oversize as what yours is especially by someone who did the quality of work that Fred Sinclair was known to do. I'd guess the neck had been opened up at a later date and hadn't been remarked.
 
Mike,
Thanks for the input. The rifle in question has been in a safe for 30 years. The original owner, who recieved it from Sinclair still has it. There has been nothing done to it. When we get some time, we'll pull the barrel and do a chamber cast. I'm not a machinist and don't have access to pin gauges.

Charlie, the neck is nowhere near .262. At this point, I just don't know how much larger it is.

Rick
 
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