Neck sizing and case getting harder to pull out?

The best way to measure setback is if your smith makes you a bump gauge with the chamber reamer. That way if you measure .002" setback, thats exactly what you will have for clearance in the chamber.
Yes I agree that is the best way. But there are some here that might not be able to afford, or justify going to a smith for this. They might not be able to even get a Precision Mic. But this could give them an idea on what's going on and adjust accordingly.
 
Yes I agree that is the best way. But there are some here that might not be able to afford, or justify going to a smith for this. They might not be able to even get a Precision Mic. But this could give them an idea on what's going on and adjust accordingly.
I hear you. The stripped bolt method works and once you know how much you have to bump the shoulder with the tools you own you can record it. The hornady comparator sets for shoulder bump and bullet seating should be required equipment, as basic as the reloading press.
https://shop.brownells.com/reloadin...Ve4S_lKr9tCqJ6EanO7eDvb5V2oJ61hoaAi0hEALw_wcB

https://www.brownells.com/reloading...r-set-sku749004951-35659-68508.aspx?rrec=true
 
Certainly good tools to have. I've gotten away with using the Precision Mic to gauge shoulder set back and mic the body on cases that feed easily. Another way to go about this is to use a RCBS X Die. All depends on what the shooter wants to do.
 
........ I have re-size reamers for wildcats that I have to make dies for but see no need with standard cartridges IF the smith is doing a good job and chambers are coming out to spec. Usually if I have a problem its not enough squeeze at the base of the case. I may only see .0003" and after a while that will cause a sticky extraction. ..........

How much smaller do you want the base of the resize reamer to be than the base of the chamber reamer?
 
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Thats trial and error and depends on the brass.
I'm surprised there isn't a more specific answer than that.

I have seen comments about ordering resize reamers at the same time a chamber reamer is ordered for Wildcat cartridges.
 
Shoulder angle, case head diameter, brass hardness, just to name a few, effect how much the case will resist sizing. No one size fits all in my experience. I know what works on a 6br wont on a 338 lapua. I have sent one resizer reamer back 3 times trying to get it perfect. There are plenty of smart guys out there that may be able to give you a scientific answer, but Im not one of them unfortunately.
 
Shoulder angle, case head diameter, brass hardness, just to name a few, effect how much the case will resist sizing. No one size fits all in my experience. I know what works on a 6br wont on a 338 lapua. I have sent one resizer reamer back 3 times trying to get it perfect. There are plenty of smart guys out there that may be able to give you a scientific answer, but Im not one of them unfortunately.
I'd much rather read your answers Alex. I can understand your concepts and language far easier than when my dad explains this stuff(aeronautical engineer). Not to mention your pictures of actual results to your explanations are fantastic also.
 
I'm surprised there isn't a more specific answer than that.

I have seen comments about ordering resize reamers at the same time a chamber reamer is ordered for Wildcat cartridges.


I rely on my reamer maker to make the re sizing reamer the correct amount smaller than the chamber reamer so there is no guessing.

He builds my wildcat reamers and re sizing reamers at the same time and can change the CNC program to reflect this change while keeping all other dimensions the same.

It is extremely difficult to measure a finish reamer dimensionaly for fear of damage to the cutting edges. I don't allow any thing to touch the reamer except a barrel and the plastic storage tubes they come in. One very small nick can cause an unwanted mark in an otherwise perfect. chamber.

Two things that I don't do anymore is buy a sizing reamer later or from someone else that did not build the original finish reamer. and never rent a finish reamer or loan my reamers out.

Just picky I guess

J E CUSTOM
 
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How much smaller does he make them?


I am not sure because I don't want to measure them for the same reason as I mentioned with finish reamers. All I can tell you is that after
using them (I have done 6 wildcats) that they have been perfect and fire formed cases gets sized perfect. I have checked the sized cases against the fired cases and It appears that they are some where between .0015 and .0025 smaller just doing a rough measurement of the two different cases before any bump. I will try to get a definitive measurement and see if the size reduction is the same across the different cartridges.

My hand made wildcat sizing reamers although a lot of trouble to make, have been excellent so I have been extremely pleased with them. I have also checked on having them made and in many cases I had to have the dies in order to load before I could fire form and the die makers that I talked to needed cases that had been fire formed at least 3 or 4 times.

On some of my wildcats that friends wanted, I used my dies to chamber and fire form their cases and fired some of there cases more than once to get a good chamber fit so they could have the cases to have a die maker make their dies.

As soon as I can get the dimensions, I will post them.

Good question ED Now I am interested to know for my self.

J E CUSTOM
 
Does your reamer maker not provide a print for each reamer?


Yes, He requires me to approve the finish reamer drawing before he will start. but i have never ask for a sizing reamer print because he always produced great reamers and knew what I needed depending on the wildcat design. (I will the next time).

J E CUSTOM
 
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