• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Shoulder not bumping back when resizing

Ok, so I just started using a set of Sinclair headspace gauges. I've been resizing some once fired .204 Ruger brass and I'm a little surprised to see that no matter how far down I take the resizing die, the shoulder will not bump back.

No matter how far down you adjust the die? Logic is logic as Truthful James said. After the die contacts the shell holder that is it. The two can not get closer once they make contact. Then there is the ability of the case to resist sizing, the cases ability to resist sizing can be more than the press can overcome; that is the reason I check the gap between the bottom of the die and top of the shell holder.

Then there is that problem; bad habits, a reloader should measure before firing and again after firing to determine the effect the chamber had on the case. After firing there is measuring before sizing and again after sizing. I suggest the reloader save a few cases for compassion. If the case chambered and fired the reloader should save a few of the unfired rounds for comparison.

F. Guffey
 
Rather than grind down the shell holder, invest in a set of Redding competition shell holders, There are 5 in a pack, one of these will bump em back just enuf.
These will not give you more bump but less. They are plus headspace. Also he has a Forester Coax press and doesn't use shell holders. Matt
 
Use a cheap Lee 22-250 AI die set. To get it right I had to grind the bottom of the sizing die down. No big deal and it has worked well for years. Of course, I use both Sinclair and Hornady sizing gauges and always remove firing pin, spring and ejector to double check the feel into the chamber.
 
I had a Krieger barrel that was like this. I was having problems bumping back enough. It was specific to that barrel. My dies were bottomed out/cammed over and it still had intermittent problems with tight cases/problems chambering. Turns out the chamber was about .005" short.
 
I had a Krieger barrel that was like this. I was having problems bumping back enough. It was specific to that barrel. My dies were bottomed out/cammed over and it still had intermittent problems with tight cases/problems chambering. Turns out the chamber was about .005" short.

.005” short from the beginning? I will never understand how something like that can escape the notice of a reloader/shooter/bench rester. .005” short for a 30/06 would mean there would be absolutely no clearance between the case and bolt face. It seems the reloader would measure the length of the case from the shoulder to the case head before firing and again after firing.

Then there is that part about bumping the shoulder back; time and time again I check the case to determine what happens to the shoulder when fired. If the shoulder moves I made a mistake. I am beginning to believe reloaders have no clue what happens when the trigger is pulled.

And then there is that story that starts with; the firing pin strikes the primer and then the whole thing including the case, powder and bullet takes off for the front of the chamber and stops when the case shoulder stops against the shoulder of the chamber; and then it goes bang.

It seems like out of all this talent someone could elaborate on the moving shoulder, I am the fan of cutting down on all that travel.

F. Guffey
 
.005” short from the beginning? I will never understand how something like that can escape the notice of a reloader/shooter/bench rester. .005” short for a 30/06 would mean there would be absolutely no clearance between the case and bolt face. It seems the reloader would measure the length of the case from the shoulder to the case head before firing and again after firing.

Then there is that part about bumping the shoulder back; time and time again I check the case to determine what happens to the shoulder when fired. If the shoulder moves I made a mistake. I am beginning to believe reloaders have no clue what happens when the trigger is pulled.

And then there is that story that starts with; the firing pin strikes the primer and then the whole thing including the case, powder and bullet takes off for the front of the chamber and stops when the case shoulder stops against the shoulder of the chamber; and then it goes bang.

It seems like out of all this talent someone could elaborate on the moving shoulder, I am the fan of cutting down on all that travel.

F. Guffey


That is how I determined the number. I made some rounds for load testing. They all had some level of difficulty chambering. Nothing that kept it from ultimately going into battery, but more snug than I would have liked.

I was meticulous (for me, but maybe not to the standards here) about working up loads for this barrel. I measured everything I could-Mic gauge, OAL, COAL, neck tension, concentricity, etc. With my mic gauge the sized brass was at 0, after firing it was still 0 with some having difficult extraction. I started bumping back incrementally until I reached .005" under and that was the point it chambered and extracted with ease. Measure with the mic, fire, measure and find out it was reseting to 0 after firing.
 
Removing the firing pin and spring allows you to feel the bolt resistance to pushing the case shoulder against the chamber shoulder. With the firing pin in the bolt the effort to compress the spring masks the effort to push the case shoulder into the chamber shoulder. With the firing pin assembly removed if you don't feel resistance to closing the bolt the shoulder doesn't need to be bumped back IMO. In other words no resistance to closing the bolt you have clearance. Sounds to me that you don't have a problem. Sometimes I think that people that have to have a lot of tools, gauges and measuring devices make up problems. I have fired at least 20 thou rounds without measuring shoulder push back?

Buy Tony Boyers book from MidWay USA, they have low shipping charges. Tony has 3 times as many Hall of Fame points as his nearest competitor. I use his method to adjust dies.

A short explanation:
1. remove the firing pin assembly.
2. Adjust your die so it touches the shell holder.
3. Back the die out maybe a half turn.
4. Get a feel for the effort to close the bolt on an empty chamber.
4. Put fired unprimed unloaded case into the rifle and close the bolt. If there is resistance to closing the bolt turn the die down a tiny amount and check resistance to closing. If there is no resistance you have clearance.
5. Keep turning the die down in small steps until you feel a very slight resistance to closing the bolt. Check the same case several times to check for spring back. You want a very small resistance to closing the bolt.

Buy Tony's book to get the proper explanation.

This is the way we did it the old days when there wasn't a lot of speciality tools available. I still believe in my humble opinion that this is very reliable way to set the shoulder back since your using the chamber directly as the gauge.
 
Copper, More information on the rifle would be helpful. Perhaps you have a "minimum" chamber in which case your brass will grow very little on firing. As others have said, strip the bolt, chamber a non-resized fired case and if there is no resistance to closing the bolt you do not need to bump the shoulder. dedogs
 
Buy Tony's book to get the proper explanation.


Before you purchases Tony’s book have someone to explain cock on open and cock on close. And then there is the difference in design. When I feel resistance to bolt closing I find the resistance to closing is caused by the ammo. I also use chamber gages because they are not expensive. I never pass up an opportunity to check barrels of barrels at the gun parts store when I am there. I find the uglier the barrel the cheaper/more affordable it is. I have no problem taking a band saw to a barrel to remove the part I do not need.


I set up at a gun show with chamber gages and no one knew what they were.


F. Guffey
 
This is the way we did it the old days when there wasn't a lot of speciality tools available. I still believe in my humble opinion that this is very reliable way to set the shoulder back since your using the chamber directly as the gauge.

Yes, using a stripped bolt and going by feel and by the relative position of the bolt handle, I’m looking to encounter a little resistance just before the bolt handle makes it to fully closed. Encountering no resistance to closing the bolt tells me the case from head to shoulder is still too short. Encounter resistance too soon whilst the bolt handle still has a fair ways to go, and the head to shoulder length is too long and that case needs its shoulder bumped back to fit that chamber.

Once I’ve got a case with a head to shoulder length I’m looking fer, I’ll grab my Hornady or Sinclair or RCBS and/or whatever instrument(s) are necessary to get me a reference measurement relative to the case head to shoulder datum length of a case that perfectly fits that chamber; and measure the thing plus make a record of the magic number, also noting exactly what instrument(s) and method was utilized in obtaining it.

Thereon, in practically no time and using exactly the same “stuff”, I can measure any case to find if it’s too short or still too long or if the fit of that case would be exactly right for that chamber, and I’ll not have to mess with stripping the bolt to check the fit of a piece of brass in that chamber ever again.
 
Click to expand...
Yes, using a stripped bolt and going by feel and by the relative position of the bolt handle, I’m looking to encounter a little resistance just before the bolt handle makes it to fully closed. Encountering no resistance to closing the bolt tells me the case from head to shoulder is still too short. Encounter resistance too soon whilst the bolt handle still has a fair ways to go, and the head to shoulder length is too long and that case needs its shoulder bumped back to fit that chamber.

Once I’ve got a case with a head to shoulder length I’m looking fer, I’ll grab my Hornady or Sinclair or RCBS and/or whatever instrument(s) are necessary to get me a reference measurement relative to the case head to shoulder datum length of a case that perfectly fits that chamber; and measure the thing plus make a record of the magic number, also noting exactly what instrument(s) and method was utilized in obtaining it.

Thereon, in practically no time and using exactly the same “stuff”, I can measure any case to find if it’s too short or still too long or if the fit of that case would be exactly right for that chamber, and I’ll not have to mess with stripping the bolt to check the fit of a piece of brass in that chamber ever again.

There are faster and easier ways.

F. Guffey
 
But they're classified!...........


I will assume you are referring to 'other methods and or techniques'; there was a smith that started checking a stack of rifles in the morning and be finished by mid morning. He measured the length of the chamber in thousandths; smiths he worked with were a snarky lot. They used the head space gage or the no go-gage and for everthing else they used the field reject length gage.

F. Guffey
 
You're not mistaking knowledge for caring are you?
e.

As I have said many times before’ I can measure the length of the chamber from the shoulder to the bolt face three different ways without a head space gage.

Mistaking knowledge for caring?; no trying to make an impossible point. There are a very few of us that can figure it out in a short period of time, then there are those that will never figure it out no matter how long they stare at it.

Anyhow, the old smith worked with a bunch of snarky smiths, had I worked with the man I would have found a nice way to ask “How do you do that?” Or “What am I doing wrong?” Anyhow, I sat down one day and worked out three different methods and or techniques for doing the same thing faster and more accurately; and not one of the three methods and or techniques are acceptable.

F. Guffey
 
Copperking81
Turn the die back up, to the point where the Co-ax press is at the cam-over point (read, bottom dead center).
Said another way; hold the press handle so the black connecting arms on the side of the press are straight up and down. Then adjust the die to firmly touch the shell holder. This will get that little bit if extra travel you need when it cams over fully.
I had the same problem with a Redding die and this was the fix from the customer service rep at Redding. It worked just fine.
CW
 
But was the ~ problem ~ due the Redding FL die or because the chamber got cut even nearer to SAAMI minimum length?
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,680
Messages
2,200,578
Members
79,045
Latest member
Paradactal
Back
Top