reamers/chambering

If it was so basic how did Hornandy screw up the PRC dimensions?
Ask Alex Wheeler how " basic" reamer designs are.
Oh there is basic, but if thats all you care about.
After dealing with Whidden, Forster and Hornady the last few years, Ive figured it out. Its not that they don't know, it about keeping things on the fat side to keep from cracking dies. Ive had to fight with them to make my Sherman dies the way I want them. Hornady will at least do that for me now, and occasionally we crack one. There is a very fine line between enough sizing and cracking the die. The reason most shelf dies, like Hornady have clickers after three firings is they look at it as good enough because the brass is toast after three firings anyway. Ive had these discussions with all of them. I reminded them that we aren't dealing with throw away brass at 2.00+ apiece and its after a few firings where the sizing becomes a problem because the case head gets harder and doesn't spring back, so you need a little more sizing than necessary the first 2 or 3 loads, but if its right, you can still size after twenty firings.
My 30 Sherman Magnum, for example only sizes an extra .0005-.001" and we have no clickers vs the PRC..
 
Look at what guys have fought with the 6BR cases when Norma got into the 6BR cases, same thing now with the newer Alpha brass. You can't just call up a reamer maker and tell them you want a 20 VT reamer either, that depends on brass unless you want problems.
Theres alot off variables to avoid problems far from " basic" unless its 1 cartridge one brass you know.
Your not gonna have clickers either if all you ever shoot is factory ammo, so if you want " basic" just order a saami reamer and shoot factory ammo.
 
I suspect that you're dumping money & time into abstracts, and then reacting to results of these abstracts as though they're causes..
Like chaos = rocket science
 
I just measure new brass & fill out a blank reamer print.
I see no reason to send a reamer maker anything other than a reamer print (through email).
Like this:
View attachment 475122
For reference you can google image reamer drawings for various cartridges.
Mike, I know you are advanced in your thinking and planning, but for those that are not, you take this drawing, make measurments on brand new brass, there is a LOT of design that still needs to be taken into account. If you have a reamer made off of exact brass dimensions, your reamer will be worthless. The print with the exact dimensions is the road map for you to now ADD clearances you want. Knowing what dimensions your dies size to is of great importance, instead of discovering a major flaw AFTER THE FACT!
You can actually make a chamber cast of the full length sizing die with Cero Safe if you are a nit pickers, nit picker.

Another issue, brass over a lot of 100 pieces may vary slightly in variations, and you need to establish a "spread" on the +/-.

Lapua
Peterson
Alpha
Winchester

have some very, very dramatic differences in dimensions, especially in the web thickness and neck thickness.

Places where many make mistakes including myself:

A. New brass dimension .200 from the bolt face, Clearance needed

B. Neck dia

C. Throat dia to take into account "fat" bullets that are oversize in the pressure ring.

NOTE: there are a LOT of mistakes made on clearance at the .200 mark from the bolt face as many make this clearance too tight for the brand of brass they are using, resulting in premature pressure indicator of hard bolt lift, and inability to Full Length resize with standard full-length sizers, This is one heck of a problem. Reloaders need a micrometer that measures to the .0001.

When a guy has a reamer that cuts for example .470 dimension at the .200 mark, then his brass measures .469, he is in for one heck of a mess, and the solution is going to a brand of brass that is .466 in the .200 mark, or trying to find a Small Base sizer for that brand of brass.

Some of the bullet companies are running their bullet-making dies to produce Fat bullets where the pressure ring is .001 over. It is not unusual to find bullets .0005 over as they are referred to Fat bullets, but to get .0010 over is a problem. For example, In my 6 Dasher varmint rifle, my throat dia is .2435, a typical throat dimension. I was having problems with a particular lot# of bullets, measured them with my micrometer, and they are .244 in the pressure ring. The bullet was being sized down as it went through the throat section, creating premature pressure spikes and simply not shooting worth a darn.

While oversize FAT bullets are not the norm, as production gets sloppy, it would pay a reloader to establish some of his own quality control.

THE major issue many face is the Web dia, new brass, fired brass, Resize dimension, and reamer/chamber dimensions. Factory rifles have more Liberal tolerances as a norm, but I have seen several undersize/tight factory chambers. All of my hunting rifles shoot some darn hot pressures at the top-end accuracy node where groups are in a Bug Hole.

European brass vs American brass, a subject for another topic

Elkaholic's problem is similar to what most go through, trying to fit a 10 lb bag of crap in a 5 lb hole. I ran into this for the first time on a 7 STW reamer that I designed to have .002 clearance in the web over new Winchester factory brass dimensions. .002 was nowhere near enough clearance, so as a fix, I was able to get one of the last 7 STW Small base sizers that came out of their custom shop that no longer exists. I got a true 0.0015 smaller case resized dimension(after spring back)vs fired brass dimension, which cycled brass just fine.

I am going to shut up for now but this problem has plagued me for 20 years on many cases. If I were rich, I could just order more reamers, but I am not, I have to figure out how to make things work where I can shoot the accuracy node the barrel likes on the cheap. This web dimension is the root cause of the misunderstandings with some using belted magnums as their chambers were just too small for their brass dimensions.

Another issue, just because a reamer print has a particular number on it, does not mean that is the dimension you get in your finished barrel due to:

Reamer wear

Gunsmithing techniques used to chamber the barrel

Reamer makers have +/-.0005 tolerance in dimensions they grind to

These three things can stack up, leading to a real mess to deal with, been there, done that!.
 
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I suspect that you're dumping money & time into abstracts, and then reacting to results of these abstracts as though they're causes..
Like chaos = rocket science
Such big words. You still didn't answer my question, did you just fill out a blank reamer print your first time?
Go over to accurateshooter and convince some of those guys its just " Basic". Ask Alex how many BRA and Dasher reamers he has and if there's a difference in them or there all just " Basic".
 
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Pacific Tool & Guage used to do this type of work. I'm not sure what they are offering today, but about 10 years ago, I sent them three brass from an 'ackley-ized' chambering in .277 caliber (based off the 338 Lapua case) and told them I wanted the same thing in .338 caliber. I got a call a week later with some additional questions and then received the reamer along with a blueprint about a month after that. I sent a copy of the print to Whidden and they made me some custom dies. Not that hard. But I have no idea what these companies are doing today.
 
Pacific Tool & Guage used to do this type of work. I'm not sure what they are offering today, but about 10 years ago, I sent them three brass from an 'ackley-ized' chambering in .277 caliber (based off the 338 Lapua case) and told them I wanted the same thing in .338 caliber. I got a call a week later with some additional questions and then received the reamer along with a blueprint about a month after that. I sent a copy of the print to Whidden and they made me some custom dies. Not that hard. But I have no idea what these companies are doing today.
I wouldnt trust P.T @ G with anything anymore.
 
After dealing with Whidden, Forster and Hornady the last few years, Ive figured it out. Its not that they don't know, it about keeping things on the fat side to keep from cracking dies. Ive had to fight with them to make my Sherman dies the way I want them. Hornady will at least do that for me now, and occasionally we crack one. There is a very fine line between enough sizing and cracking the die. The reason most shelf dies, like Hornady have clickers after three firings is they look at it as good enough because the brass is toast after three firings anyway. Ive had these discussions with all of them. I reminded them that we aren't dealing with throw away brass at 2.00+ apiece and its after a few firings where the sizing becomes a problem because the case head gets harder and doesn't spring back, so you need a little more sizing than necessary the first 2 or 3 loads, but if its right, you can still size after twenty firings.
My 30 Sherman Magnum, for example only sizes an extra .0005-.001" and we have no clickers vs the PRC..

I know this is spot on.....I bet there's more Redding Small base 284 cracked dies than you can stir with a stick!!

The old school way of thinking is tight everything.....now we know a little clearance in the right areas make a world of difference. Especially at the .200 line and the free bore diameter......common place is .001 over bullet diameter these days.
 
What Sherm is speaking of is "Ring dies", and it would be nice to have then graduated in .0005 sizes. I approached Whidden about this issue, seems to be a can of worms for heat treat, or ? as dimensions change.

Sherm could comment on heat treat issues, I am sure.
 
Such big words. You still didn't answer my question, did you just fill out a blank reamer print your first time?
Go over to accurateshooter and convince some of those guys its just " Basic". Ask Alex how many BRA and Dasher reamers he has and if there's a difference in them or there all just " Basic".
I learned about SAAMI tolerances and wildcats of the time in a reloading class. This was 1975, I was 12.
But I'm sure nothing in reloading has advanced beyond basic in over 100yrs.
Same kind of people, with their same kind of folklore, and their same bad choices.

Give me one technical basis for more clearance being in your answers.
Not a so & so says it, or had a problem or won with it, but your actual understanding of what goes on with clearances and gun design.
 
I learned about SAAMI tolerances and wildcats of the time in a reloading class. This was 1975, I was 12.
But I'm sure nothing in reloading has advanced beyond basic in over 100yrs.
Same kind of people, with their same kind of folklore, and their same bad choices.

Give me one technical basis for more clearance being in your answers.
Not a so & so says it, or had a problem or won with it, but your actual understanding of what goes on with clearances and gun design.
Everbody i know in LR BR is gotten away from tight necks, tight brass dimensions etc.
Eric Cortina says he runs. 006 nk clearance know.
Like I said you obviously don't believe me ask the guys at the top of the BR game.
Nobody even nk sizes anymore, very very few.
 
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