Yet another shoulder bump question

[Lance21]

Just a hunch here, I'm thinking it's your annealing method. You can time the duration in the flame but that doesn't guarantee it's the same temperature. As gas levels go down your temperature will change also. I had a flame annealer once. It caused so many problems. I couldn't sell it fast enough! If you can swing it get an Amp annealer. I know they're expensive but the consistency you'll get will be worth it.

 

[DLT]

Before you go out and spend a ton of money on more equipment, I've using standard RCBS die with expander balls for 50+years without any issue whatsoever.

Expander Ball Discussion:
Are you getting any significant drag on the expander button? If so, are you lubing the inside of the case neck? Most expander balls are oversized and have a rough surface. I polished mine with very fine emery cloth to produce a "glass like finish" which significantly improves expander the neck without lengthening it. Also, by reducing it .001" often produces better fit.

Sizing Discussion
What are the fired datum line measurements versus the sized measurements? If the die is not touching the shoulder, then you could be extruding (lengthening) the case. You don't need to purchase competition shell holders. You can adjust your sizing die in small increments to find the optimum shoulder set back.

Although you don't need these either, I use Ship Shims which fit under the lock ring of the die to simplify making sizing corrections. These range from .003" to .010" and provide a full range of easy adjustment without having to reset your FL die. Available at Brownell's and are much cheaper than competition shell holders and quite frankly work better, at least for me.

I cannot comment on annealing since I don't use this process, but I wonder if any inconsistency in the process could be causing a problem.

The only thing I can think of that's causing the first sizing to be off is that you have a lot of flex in the press, or the sizing die in working loose, or you do not have sufficient cam over so that the die is at least touching the shoulder, or somehow the annealing is affecting the consistency of the brass but as I said, I do not anneal so this comment may not be applicable. It would be interesting to see the fired datum line measurement and the sized measurements. Is the shoulder being pushed back enough and consistently?

With this die all cases feel fine and pretty smooth coming over the expander ball. I was trying another route to setup the sizing die, I’m pretty sure I never measured the datum line of my fired cases I was carefully screwing the die in little by little each sizing to get the striped bolt to fall with no resistance. I do know that using the hornady headspace tools the bolt would close with very little resistance bumped to 1.450. Zero resistance at 1.449 that I could feel. The shims your talking about, are they just for fast adjustment or could they get the shell holder to contact the die. I have around .010 gap between my shell holder and die currently

 

[Lone Hunter]

Here are the shims K22 is talking about.

Skip's 7/8-14 Sizing Die Shims

This set of seven 7/8 die shims enables you to set the die up once, then adjust the die in small, exact increments without loosening the die lock ring and starting over.

benchrite.com

 

[DLT]

I am not familiar with your press. I watched the video by MEC and am puzzled by the fact that once you hit TDC the handle will still move lower. Your press might not have true cam-over. My Redding Boss press has a roll pin stop that can be removed and the ram will go past cam-over. I tried it that way, but put the roll pin back so it provides cam-over. The Rockchuckers have the bottom link hitting a linkage strut- Both my presses have a hard stop -preventing the handles from further movement which means the ram is at TDC.

I might be mistaken but I don’t think the marksman press I have is like that. Once the handle is all the way down the ram is all the way up. UNLIKE say a rock chucker press. I don’t think I am but I could be.

 

[LHSmith]

Skips shims go under die -you have to remove die to use.

 

[DLT]

Just a hunch here, I'm thinking it's your annealing method. You can time the duration in the flame but that doesn't guarantee it's the same temperature. As gas levels go down your temperature will change also. I had a flame annealer once. It caused so many problems. I couldn't sell it fast enough! If you can swing it get an Amp annealer. I know they're expensive but the consistency you'll get will be worth it.

I appreciate it and I hope that’s not what’s causing it. No way I would go that route for no more involved than I am.

 

[DLT]

Here are the shims K22 is talking about.

Skip's 7/8-14 Sizing Die Shims

This set of seven 7/8 die shims enables you to set the die up once, then adjust the die in small, exact increments without loosening the die lock ring and starting over.

benchrite.com

Yea. That’s what I thought. I always thought they was for making fast adjustments. I don’t see how they could help in my situation OR I don’t understand. If I screw my die down to my shell holder to get some cam over it would bump my brass too much either with the shims or not. Right ?

 

[J.d. Popkes]

Are you going to try it? 3 cases.

 

[LHSmith]

In the Q&A section it states the press does have cam-over. I anneal like you do. IMHO I don't believe that is the issue as long as you address the fact that the cases get "sticky" after anneal. I tumble mine after.

 

[DLT]

Are you going to try it? 3 cases.

Sure I’ll try it. Might be tomorrow. I’ll take the guts out of my die, Screw it down to get good cam over, and size 3 cases and measure them. How mine is now. It might size 7/10 correct

 

[DLT]

In the Q&A section it states the press does have cam-over. I anneal like you do. IMHO I don't believe that is the issue as long as you address the fact that the cases get "sticky" after anneal. I tumble mine after.

I really need to check into that. A rock chucker press, correct me if I’m wrong but as the handle is getting pulled down the ram gets to top dead center then drops slightly when the handle bottoms out ?????

 

[LHSmith]

Yea. That’s what I thought. I always thought they was for making fast adjustments. I don’t see how they could help in my situation OR I don’t understand. If I screw my die down to my shell holder to get some cam over it would bump my brass too much either with the shims or not. Right ?

I set my die so it just touches the S/H. If I need more bump I add 0.001" of shim at a time and it is very repeatable albeit a pita to keep removing the die. In a normal loading for a match of 60 cases I might have to bump just a couple a thou more and 2 or 3 0.002" more bump. I have too many cartridges to go to the expense of Comp. S/H's and they are only in increments of 0.002". PMA also makes a micro-adjuster that goes between the press and die.

 

[DLT]

I set my die so it just touches the S/H. If I need more bump I add 0.001" of shim at a time and it is very repeatable albeit a pita to keep removing the die. In a normal loading for a match of 60 cases I might have to bump just a couple a thou more and 2 or 3 0.002" more bump. I have too many cartridges to go to the expense of Comp. S/H's and they are only in increments of 0.002"

See I’m lost. If you set your die to touch the shell holder and you need more bump if you add a shim under the lock ring isn’t that decreasing your bump or am I looking at it backwards ?

 

[DLT]

In the Q&A section it states the press does have cam-over. I anneal like you do. IMHO I don't believe that is the issue as long as you address the fact that the cases get "sticky" after anneal. I tumble mine after.

Send a link to that if possible. Thanks

 

[INTJ]

Anybody who measures each piece of brass after sizing will find variation. Factors that influence variation include brass variance, lube variance, press flex, and press technique.

I have a Prazipress that has no deflection. Even with sorted brass, annealing with AMP-AZTEC, consistency in how I pull the handle, and consistency in lube I will still get variation. My variation was cut in half when I went from a Forster CoAx to the Prazi.

All that said, last week I prepped 100 once fired Lapua 6BRA cases. The fire forming on these will get the shoulder fully formed but the base is still .002" undersize. (It needs one more firing to get the bases fully formed).

Anyway, 99 pieces sized the same and one was .0005" long. That is the most consistency I have ever seen, and I think it was due to the undersized bases. There was very little resistance when pulling the press handle.

My fully formed 300 SAUM IMP cases require noticeable more force to size, and they come out less consistent. I just make sure to set the die so that any inconsistency is to the plus side, and then I can size them a second time to correct that.

 

[LHSmith]

I really need to check into that. A rock chucker press, correct me if I’m wrong but as the handle is getting pulled down the ram gets to top dead center then drops slightly when the handle bottoms out ?????

No that is how the Redding Boss works IF you remove the roll pin. The Roll pin provides the stop for cam-over.

See I’m lost. If you set your die to touch the shell holder and you need more bump if you add a shim under the lock ring isn’t that decreasing your bump or am I looking at it backwards ?

OK, the shims start at 0.003" thickness, so you set up the die with a multitude of shims, then to bump a thou more for example replace a 0.005 shim with a 0.004 shim thereby moving the die closer to the S/H.

 

[DLT]

No that is how the Redding Boss works IF you remove the roll pin. The Roll pin provides the stop for cam-over.

OK, the shims start at 0.003" thickness, so you set up the die with a multitude of shims, then to bump a thou more for example replace a 0.005 shim with a 0.004 shim thereby moving the die closer to the S/H.

That makes a lot more sense

 

[LHSmith]

Send a link to that if possible. Thanks

MEC Marksman Single Stage Reloading Press

As an industry-leading manufacturer of shotshell reloading equipment and clay target machines, MEC brings its knowledge and expertise to the metallic...

www.midwayusa.com

 

[DLT]

MEC Marksman Single Stage Reloading Press

As an industry-leading manufacturer of shotshell reloading equipment and clay target machines, MEC brings its knowledge and expertise to the metallic...

www.midwayusa.com

I seen that. Mine is a hard stop press. The ram doesn’t go down at all unless the handle goes up. The rock chucker is considered a cam over press though

 

[Webster]

I appreciate it and I hope that’s not what’s causing it. No way I would go that route for no more involved than I am.

Were do you get the .450" measurement? Never understood over camming. Don't like mandrels. I used a Redding FL bushing die for the last 10 years a STD FL die without an expander ball or mandrels before that.. Never had any problems reloading for 50 years. Buy a bump gauge. If you want to use a mandrel I would lube it with something to make sure you are not pushing the shoulder a few thou. I always lube the shoulder and neck . It might be possible while sizing the neck the force on the neck may push the shoulder back a few thou? Slop in the linkage? I assume when you pull the handle all the clearances get bottomed out and the ram comes up the same amount you set up.