Help with Shoulder Bumping

[918v]

I'd do everything 918v just stated here other than be smart about it while using a headspace gauge and tune your reloads to your rifle for improved accuracy while increasing the lifespan of your brass. Other than that, 918v is about 1/2 correct

Elfster1234:

We're both talking about a .010" range of die adjustment. Zero is where I feel the bolt drag. Your zero is what you measure on a fireformed case. We're both adjusting the die incrementally. Me, until I don't feel the bolt drag. You, until your measuring device says you've bumped the shoulder a specified amount. In both methods of die adjustment, we're going incrementally. The only difference is is where we decide to stop. Me, it's when I feel clearance. You, when your measuring device tells you to. We then lock down the die setting. In both cases, once the die is set and locked, the press linkage slop and press window flex and the brass spring back will cause the amount of shoulder bump to vary.

Just because you think you've bumped the shoulder .004" does not mean the next case will have been bumped .004".

Because you are not bottoming out the shell holder, your .004" number is not constant. It is .004" for the case you just sized, but not for the next one. It may be more or less due to press linkage/springing/brass hardness issues.

Again, I'm not saying I can tell what .001" feels like, but I can tell what a "minimal" amount well short of the .010" system limitation feels like. I actually bottom out my die against a +.006" competition shell holder that gives me a .002" annealed shoulder bump. I anneal and body size after every firing and my cases grow about .002" per firing. My bolt closes easily, without drag. My brass lasts a long time.

What I don't appreciate, Elfster1234, is you implying that 100 years worth of metallic cartrige reloading has been unsafe until you discovered a new way using gauges.

 

[elfster1234]

are we talking bolt actions or AR's in terms of being sub-moa all day long? I'm talking AR's and semi-autos in which, as of this very second, that's all I own... to get "sub-moa" (30 shots in a row or 6 total 5shot groups in a row) all day long on my shootout threads with 3 total 5.56 AR's and 1 total 7.62 LMT is just not hit or miss.. most of it is due to my reloading techniques as I see massive accuracy swings dependent upon the ammo used....

now, if we are talking bolt actions... then yes... get some factory ammo and start shooting sub moa all day long... its a whole different story with a .308 semi auto AR..

more than welcome to join the shootout threads and show your stuff. I'm currently running both bolt action and semi auto shootout threads.

you don't get 99 out 100 shots (20 total 5shot groups) fired in a row sub-moa like this out of a semi-auto AR (mind you not a bolt action), with different varget drop rates by simple "guessing" and "feeling" your way to accuracy:

I have no problems getting sub moa out of my rifles with the other method mentioned above either. I don't shoot of sandbags like some people so I can't tell the difference between your method and my method lol. My point is simply because it's not your way doesn't mean it's wrong. Look at factory ammo people use for matches, it's not headspaced for one particular chamber and people win with it so that tells me it doesn't matter. Yeah my brass might be overworked but I don't give a shit since the primer pocket will most likely go first.

 

[elfster1234]

this is spot on

I wasn't going to get into this, but I'll explain why I use bump gauges. I've been reloading for 40 years. I reload for 15+ rifle calibers and have multiple rifles in the same caliber.

Many years ago, I started using the Wilson type drop in gauges because I was getting cases stuck in rifle chambers. The Wilson gauges got me in the ballpark, but when reloading for precision rifles, they leave a little to be desired. I know you can use a caliper on the gauges to get more precise readings, but I found them difficult to use that way and used the feel method.

If you own one rifle, you can do the old method of trial and error that 918v likes to use. It will work, but you still don't know exactly where you are.

I use the Hornady and Sinclair bump gauges. When used with a set of digital or good dial calipers, they will show you exactly where you are down to the .001". for the 15+ calibers I reload for, These gauges will work on them all.

In my calibers that I have multiple rifles, all I have to do to change the shoulder bump for a particular rifle I have measured and noted (all of my rifles have binder notebooks for references) the fired case shoulder measurements on is use either a Redding competition shell holder or a Skip's die shim to adjust the amount of shoulder bump for that particular rifle. It works quite fast and the numbers are there looking at you in the face. Quick, easy and precise. Today, If I get a sticky case, all I have to do is put the case in the gauge and the numbers will be there.

Just using the die manufacturer's recommendation of touching the shell holder and then some is nonsense. Over the years, I had a 6MM Remington and a 338 Winchester magnum that got case head separations after 3 firings by using that method. Decades later, I now understand the chambers in these two rifles were a little generous and I was oversizing the brass and it failed after a few firings.

I have over 30 rifles I reload ammunition for. The Hornady bump gauge cost me about $30.00 years ago. Today, it costs about $45.00, to me that is money well spent to have a gauge set that works on all of my calibers.

For me the whole reason to use gauges is to avoid a stuck, loaded case in the chamber and have to beat on the bolt handle or Mortar an AR to get the case out also not to over work my brass and avoid case failures. I've done all of the above over the decades and it pisses me off when it happens. Gauges help me identify any issues.

I guess what I'm trying to say is if you reload for more than one Rifle, It's really fucking stupid not to use some sort of gauge with so many relative inexpensive gauges out on the market.

Another reloader said something which I believe is very true:

"Reloading without mics, gauges and chrono's is like flying without navigation gear. You spend a good portion of the time not knowing where you are."

 

[elfster1234]

I think if I was you 918v is to keep on doing what you're doing... just don't be around me when you're doing it.

Elfster1234:

We're both talking about a .010" range of die adjustment. Zero is where I feel the bolt drag. Your zero is what you measure on a fireformed case. We're both adjusting the die incrementally. Me, until I don't feel the bolt drag. You, until your measuring device says you've bumped the shoulder a specified amount. In both methods of die adjustment, we're going incrementally. The only difference is is where we decide to stop. Me, it's when I feel clearance. You, when your measuring device tells you to. We then lock down the die setting. In both cases, once the die is set and locked, the press linkage slop and press window flex and the brass spring back will cause the amount of shoulder bump to vary.

Just because you think you've bumped the shoulder .004" does not mean the next case will have been bumped .004".

Because you are not bottoming out the shell holder, your .004" number is not constant. It is .004" for the case you just sized, but not for the next one. It may be more or less due to press linkage/springing/brass hardness issues.

Again, I'm not saying I can tell what .001" feels like, but I can tell what a "minimal" amount well short of the .010" system limitation feels like. I actually bottom out my die against a +.006" competition shell holder that gives me a .002" annealed shoulder bump. I anneal and body size after every firing and my cases grow about .002" per firing. My bolt closes easily, without drag. My brass lasts a long time.

What I don't appreciate, Elfster1234, is you implying that 100 years worth of metallic cartrige reloading has been unsafe until you discovered a new way using gauges.

 

[Bradu]

I don't recall this being a discussion of just ar's but since you want to try to help your case by just saying ar's lol, here is a couple examples. The two ar's I had, a GA precision built ar-10 would run sub moa with FGGM along with an RWS built ar10 that had no problems running sub moa using Copper creek or Southwest ammo. I know I am not the only one shooting factory ammo with a Gap built ar running factory ammo and shooting sub moa.

 

[Bradu]

I suppose now you want to say that custom built ar's don't count??

 

[elfster1234]

like ive always said and honestly not being cocky here... talk the talk, walk the walk... run your factory or what ever reloads on the bolt action or semi-auto shootout threads... getting sub-moa here and there, and doing it consistently is two different things and the whole reason for starting the shootout threads. it wasn't until I started using my current reloading techniques did I actually start to see HUGE accuracy improvements... and this is with a $950 rock river arms rifle... not a $3000 plus dollar GAP.

I don't recall this being a discussion of just ar's but since you want to try to help your case by just saying ar's lol, here is a couple examples. The two ar's I had, a GA precision built ar-10 would run sub moa with FGGM along with an RWS built ar10 that had no problems running sub moa using Copper creek or Southwest ammo. I know I am not the only one shooting factory ammo with a Gap built ar running factory ammo and shooting sub moa.

 

[Bradu]

First off I sold my ar-10's and second, your threads about shooting groups is a waste of ammo. You brag about your LMT groups which probably cost the same as what I paid for my GAP so don't give me the line about just cheap ar's. The only groups I shoot are for load testing and I don't have anything to prove. My rifles shoot great using factory ammo or my improperly loaded reloads lol.

 

[elfster1234]

it doesn't really matter to me what rifle you use... the supplied picture was done with a $950 rock river rifle and my reloads... not a $3k plus GAP or custom what ever... a massive amount of this is due to reloading. and I have other pictures just like this for every single $1k rock river / DPMS rifle I own due to reloading. not being cocky... I just like walking the walk... not just talking a bunch of BS (not saying you're are talking BS, just myself.)

I suppose now you want to say that custom built ar's don't count??

 

[elfster1234]

im sorry, but this means absolutely nothing to me. LOL

if you're going to talk, then you better be ready to put foot to ass

First off I sold my ar-10's and second, your threads about shooting groups is a waste of ammo. You brag about your LMT groups which probably cost the same as what I paid for my GAP so don't give me the line about just cheap ar's. The only groups I shoot are for load testing and I don't have anything to prove. My rifles shoot great using factory ammo or my improperly loaded reloads lol.

 

[bigedp51]

Can't help you with the headspace measuring thingy as it is unnecessary.

You don't need a tricky gauge. All you need is your brain.

This "thingy" below doesn't have a brain and is accurate to .0005 and I don't have to play with my bolt to "SEE" the digital readout.

Basics: Headspace
Setting Proper Headpace on Resized Cases
by Germán A. Salazar

The Rifleman's Journal: Basics: Headspace

Imagine a real live competitive shooter with lots of headspace measuring thingies.

 

[918v]

I think if I was you 918v is to keep on doing what you're doing... just don't be around me when you're doing it.

Doing as in bottoming out my die against a +.006" shell holder?

You're afraid of that?

This proves that you in fact do not understand case sizing.

 

[918v]

This "thingy" below doesn't have a brain and is accurate to .0005 and I don't have to play with my bolt to "SEE" the digital readout.

Basics: Headspace
Setting Proper Headpace on Resized Cases
by Germán A. Salazar

The Rifleman's Journal: Basics: Headspace

Imagine a real live competitive shooter with lots of headspace measuring thingies.

Feeling the bolt face drag on a case head indicates zero more accurately than your thingy, reason being the case is inside the actual chamber and not some thingy. What you're doing is using a model to predict an outcome. You are theorizing. I'm actually doing it.

There is a reason Redding sells these competition shell holders.

And you too ignore the press linkage slop/ press springing / brass hardness issue. Wonder why?

 

[bigedp51]

918v

I use my Redding competition shell holder every time I reload and my cartridge case headspace gauge "thingy" sits on the reloading bench and I measure each case hot off the press 'WITHOUT' picking up any rifles and "GUESSING" if I have .001, .002 or .003 thousandths shoulder bump. So tell me, how do you "feel" the shoulder bump "airspace" between the bolt face and the rear of the case.

So now I'm going to tell you a true story about life and keeping up with technology.

In the early 1980s I was putting a record on my top of the line 1972 vintage stereo bought in the BX in Japan before I got out of the service. My turntable was a German Dual 1229 with a 12 pound platter and the best you could get at the time.

As my young son was watching me put a record on the turntable and getting ready to tape the record on my Akai reel to reel tape deck, he said "Dad you should get a CD player". I turned around and gave my son the best fatherly "I'm a lot smarter than you look" and said don't worry son those CD players will never catch on and digital music will never sound as good as analog music.

I'm going to keep using my digital headspace thingy and remember the vinyl records are in a box in the furnace room gathering analog dust.

 

[918v]

918v

I use my Redding competition shell holder every time I reload and my cartridge case headspace gauge "thingy" sits on the reloading bench and I measure each case hot off the press 'WITHOUT' picking up any rifles and "GUESSING" if I have .001, .002 or .003 thousandths shoulder bump. So tell me, how do you "feel" the shoulder bump "airspace" between the bolt face and the rear of the case.

I feel bolt face drag closing the bolt on a fireformed case.

I can't close the bolt using the +.010" shell holder.

I feel bolt face drag using the +.008" shell holder. It feels the same as an unsized case.

I do not feel any bolt face drag using the +.006" shell holder.

I conclude that I have anywhere from .001" to .002" of clearance that way, depending on the amount of brass springback.

That's a lot more precise than what Elfster1234 is doing.

 

[ZombieMonkey]

I've measured a large number of fired and resized cases and this method plain works and it is repeatable and not done by "feel." If you're telling me that the +/- 0.0005 variance I see after resizing on any of the presses I have used this method for reflects any slop in the press, then I give up.

The manufacturers directions to screw the die into the shell plate all the way on a sizing die are done that because it's an easy way for them to attempt to bubba proof the setup of their dies. It is not a guarantee that you will not have an issue. I've had dies out of spec that result in excessive shoulder bumping or not enough because they are out of spec. The only way to properly determine this is by measurements, feel will not get you there with a bolt action that has an action that has a strong camming force as they can mask an issue. Semi-auto's are impossible to setup by feel.

The manufacturers setup instructions will not help you identify any issues nor will it yield you the brass life that the methods some of us are advocating will get you.

Someone asked for help with shoulder bumping by posting this thread. You know how much easier it is to explain to someone how to properly adjust their die using verifiable measurements rather than by feel? Try to explain to someone having issues how they can reliably setup their dies by feel when they have no clue what exactly that feel is. At that point, they are winging it and good luck to them.

 

[Limedust]

918v

I use my Redding competition shell holder every time I reload and my cartridge case headspace gauge "thingy" sits on the reloading bench and I measure each case hot off the press 'WITHOUT' picking up any rifles and "GUESSING" if I have .001, .002 or .003 thousandths shoulder bump. So tell me, how do you "feel" the shoulder bump "airspace" between the bolt face and the rear of the case.

So now I'm going to tell you a true story about life and keeping up with technology.

In the early 1980s I was putting a record on my top of the line 1972 vintage stereo bought in the BX in Japan before I got out of the service. My turntable was a German Dual 1229 with a 12 pound platter and the best you could get at the time.

As my young son was watching me put a record on the turntable and getting ready to tape the record on my Akai reel to reel tape deck, he said "Dad you should get a CD player". I turned around and gave my son the best fatherly "I'm a lot smarter than you look" and said don't worry son those CD players will never catch on and digital music will never sound as good as analog music.

I'm going to keep using my digital headspace thingy and remember the vinyl records are in a box in the furnace room gathering analog dust.

Digital music sounds nowhere near as good that played on quality analog equipment. Digital is convenient and cheap. Do you still have your stuff?

I too wonder about the die instructions in regards to elfster1234s posts about danger. Are the hobby reloaders following such instructions kabooming with any more frequency than the diminishing returns crowd?

 

[haroldwilson]

A caliper is not accurate to .0005". Period. It may read that many decimals, but it does not have that accuracy. I agree with your methodology completely, but you are not measuring to .0005".

 

[ZombieMonkey]

A caliper is not accurate to .0005". Period. It may read that many decimals, but it does not have that accuracy. I agree with your methodology completely, but you are not measuring to .0005".

You are correct, the digital caliper has a resolution to 0.0005, but the accuracy of the actual reading is +/- 0.001. The readings all come out within that stated resolution on the digital caliper, however I cannot truly say that it is less than 0.001 as that's the accuracy level listed by the manufacturer.

 

[918v]

If the accuracy is +/-.001", then the .004" figure cited by Elfster1234 could be .003" or .004" or .005", well within range of the "feel" method.

A better method is the competition shell holder method.

If neither tool is available, setting the die by feel will result in minimal clearance. No, you won't know where you are exactly, but you'll be in the same spot as the guy with the gauge.

A 7/8x14" die can only go so deep in one turn. Knowing that fact, one may set the die quite precisely and with repeatability. There are numerous landmarks on the die and the lock ring one can reference. Your dial caliper has a depth gauge.

 

[918v]

A quarter turn of the die results in .018" of shoulder bump, theoretically. So the range of die adjustment we're working with is full std shell holder contact minus one eighth of a turn.

1/8th of a turn is the equivalent of eight knurl diamonds on a Redding die. So each knurl diamond is worth .001" of shoulder bump.

Am I wrong?

 

[ZombieMonkey]

The competition shell holders have their place using the method of bottoming out the die assuming you are using when you use a gauge to verify that a give shell holder is giving you what you are asking for in return. You cannot just blindly use feel to select which of those shell holders is appropriate. The bottoming out of the die is not my main concern if you're using a competition shell holder as they are designed specifically for that. Using the feel to determine which shell holder would be appropriate is what I have an issue with or blindly. Just telling someone to bottom out the die and to use feel is not a case of best practice. If it's working for you, more power to you. However, I will never advocate doing that in the case of bottlenecked cases when someone is looking for help.

 

[918v]

The competition shell holders have their place using the method of bottoming out the die assuming you are using when you use a gauge to verify that a give shell holder is giving you what you are asking for in return. You cannot just blindly use feel to select which of those shell holders is appropriate. The bottoming out of the die is not my main concern if you're using a competition shell holder as they are designed specifically for that. Using the feel to determine which shell holder would be appropriate is what I have an issue with or blindly. Just telling someone to bottom out the die and to use feel is not a case of best practice. If it's working for you, more power to you. However, I will never advocate doing that in the case of bottlenecked cases when someone is looking for help.

Why not?

Did you read post #65?

 

[918v]

How about post #71? Did you read it?

 

[bigedp51]

This posting needs to get down to basic headspace reference material caused by unscrupulous bartenders in dimly lit bars.

And then work up to 1/2 inch shoulder bump problems.

I wonder what that would feel like in 918v chamber?

I'm sticking with the cartridge should fit the chamber like a rat turd in a violin case and skip all this other shit.

George Carlin said it best with his high school cheerleading song

RAT SHIT! BAT SHIT! - YouTube

 

[918v]

This posting needs to get down to basic headspace reference material caused by unscrupulous bartenders in dimly lit bars.

I've been pretty lucky with my .308's. They were all within .002" of eachother chamberwise. Factory ammo would chamber with zero clearance often, especially Hornady match.

I don't want to fight anymore.