How to accurize the press?

[TaperPin]

Like any machined collection of parts, especially the mass produced ones, no press is perfect. I’ve been guilty of assuming my rock chucker is just fine, but it’s time to go through it, case holders, dies, even the primer seater stem. What have you guys checked and what was the most surprising? What did you do about it?

Is the end of the ram square and flat? Heck, is the ram even straight? How much slop in the ram is ok? Is the shell holder centered on the threads for the dies? Are those threads straight? Is the bearing surface true to the bore and flat? How true is the interior to the exterior to the bearing surface of the nut?

Which of the major makers has the best machining?

 

[Straightshooter1]

Like any machined collection of parts, especially the mass produced ones, no press is perfect. I’ve been guilty of assuming my rock chucker is just fine, but it’s time to go through it, case holders, dies, even the primer seater stem. What have you guys checked and what was the most surprising? What did you do about it?

Is the end of the ram square and flat? Heck, is the ram even straight? How much slop in the ram is ok? Is the shell holder centered on the threads for the dies? Are those threads straight? Is the bearing surface true to the bore and flat? How true is the interior to the exterior to the bearing surface of the nut?

Which of the major makers has the best machining?

You mention a lot of good issue that are at play. The best comparison report that I've seen so far is this one that Ultimate Reloader did here (note the "Press Overviews at the bottom page 1):

Fourteen Reloading Presses Compared: Single-Stage Shootout – Ultimate Reloader

ultimatereloader.com

 

[Bill Norris]

The best mods I have done to my Rock-chucker Supreme is pictured here. First of all I went thru it and tightened up the linkage to reduce the play. Then as seen in the pic I shimmed the front of it to make sure it was sitting level on the bench. Front to back and side to side. Lastly, I removed the spring clip from the ram and replaced it with a proper-sized O-ring to hold the shell holder in place. I placed a small magnet behind the ram to assure the shell holder was retracted back to center each time I remove a case.

 

[Straightshooter1]

For my Forster Co-Ax, I've rotated dies to a position that produces the best results and marked the dies position in the press so that when I insert the die into the press again, I'm sure it's exactly the same position. This tends to give me repeatable good results from my press and die combination.

 

[Zero333]

O-rings under the lock ling of the die and under the crew that tightens up the decapping pin. Don't over tighten the o-rings because you want them to float and have some movement to compensate for the
concentricity. You can also use the lower most o-ring to move the die several thou each way.

 

[NZ_Fclass]

A magnet - I need a10in screwdriver to shift the shell holder on my Rockchucker!

 

[jimmymac]

This is a subject that is near and dear to my heart. For the vast majority of my reloading I use a cheap RCBS Partner press. The one thing that was done to it is the top of the press was squared up to play nice with the die. A creative gunsmith I know does this work to Partner presses. This press itself couldn’t be any sloppier in operation but that’s not a bad thing. It’s reloaded many thousands of BR quality rounds

In case you can’t tell, I’m firmly in the camp that believes the die does the actual work to the brass and the press is just the means to that end. A sloppy ram and a nice squared up die is hard to beat. Don’t believe that? Go to a short range BR match and you may be surprised how many Partner presses you still see in use. If they weren’t capable of making good ammo, they wouldn’t exist in that arena.

Presses are just another thing us reloading types tend to obsess over to create solutions to problems that most likely don’t exist. It’s easy enough to verify the end result by the brass that comes out of the die at the end of the sizing operation.

 

[Ned Ludd]

Like any machined collection of parts, especially the mass produced ones, no press is perfect. I’ve been guilty of assuming my rock chucker is just fine, but it’s time to go through it, case holders, dies, even the primer seater stem. What have you guys checked and what was the most surprising? What did you do about it?

Is the end of the ram square and flat? Heck, is the ram even straight? How much slop in the ram is ok? Is the shell holder centered on the threads for the dies? Are those threads straight? Is the bearing surface true to the bore and flat? How true is the interior to the exterior to the bearing surface of the nut?

Which of the major makers has the best machining?

I'm not really concerned about any of these things, because I have no reason to be. My Rockchucker loads ammunition with minimal to zero runout that shoots with better precision than I can. The performance of this ammunition is demonstrated regularly in competition. Checking everything out as you're describing may be necessary at times, but I would let the performance of the press tell me something was wrong before I undertook such an exercise. I evaluate the performance of the press via the ammunition it produces. Unless there is some definitive problem with the press as quantified by a specific defect/anomaly of the ammunition it produces, I would not attempt what you're describing without good reason. I would also add that having a good reason would likely point one in a certain direction, such that a total check/overhaul of the press would be unnecessary anyhow. Maintenance is one thing, what you're describing goes far beyond that. Even more, it seems as though such an exercise could leave you second-guessing your equipment. I'm not sure that's a place you really want to go.

Just for a moment, let's say you go through the whole evaluation process and find something you don't like, or that seems out of true, or just not what you think it should be. What then? Unless loaded ammunition exhibits some measurable and well-defined issue, how will you know that whatever it was you found actually was causing any problem? And how will you "correct" it if it isn't causing a specific quantifiable defect that can be detectably corrected or improved? Along the same line of reasoning, I know a few individuals that have purchased very expensive high-end presses, or other kinds of reloading equipment. The ammunition this equipment produced didn't perform any better in their hands than whatever they were using before, as gauged by their match scores. That is not to imply that there is anything wrong with high-end presses or other reloading equipment, or that these items can't offer some kind of improvement or benefit over more modestly priced offerings; they clearly can in some cases. In no way do I mean that they are completely without benefit. I simply mean that if a given reloading press itself is NOT the limiting source of error in the ammunition produced, then a higher priced model of press is not likely to fix the problem. Just something to think about before going down this road.

 

[M-61]

but it’s time to go through it, case holders, dies, even the primer seater stem. What have you guys checked and what was the most surprising? What did you do about it?

Not a thing. Accurate ammo may come from the die. How you insert and withdraw the brass in the die I feel is totally irrelevant. Though not a fan, Wilson dies show that.
I’ll have to use the case holder but a beat up vise on a bench will insert and withdraw the case to as accurate dimensions as the prettiest press. How on earth are you deforming a die? Loose linkage? Sloppy ram. That die is some hunk of steel. Some engineer on here should be able to figure out what force it takes to bend a die. If you insert the case on an angle due to slop and a crooked ram how far is that case going until the die wins?
I do like the way the presses look over a vise .

 

[R.Morehouse]

Custom dies are where it's at for me. I use a pair of Hollywood Senior presses and a little blue RFD. If I switch shell holders from one Hollywood to the other they size within 1K of each other......I know that has ZERO significance to what we are talking about......I just think it's cool.......Keep your press clean from debris and have custom dies made for your chamber and you will be well ahead of the game......IMHO

Regards
Rick

 

[jackieschmidt]

A press has but a few basic functions.

Number one is it furnishes the power to insert and remove the case from the die.

The dies have the specific function of sizing the case properly and insuring consistent seating depth.

Number Two is during this function, the press must allow the dies to do their job with the least amount of interference as possible.

Be willing to check your loaded rounds. Arrive at a number you can live with, and see if your equipment is meeting this standard.

I have read information in threads where shooters have bought the best of everything, and still found runnout in loaded rounds. Usually in the neighborhood of .003 tp .005 inch.

The discussion then drifts into “does that amount of runnout really matter”?

It sure doesn’t help. But does it really show up on the target?

However, .003 to .005 variation in seating depth does matter in extreme accuracy shooting.

So concentrate on the aspects of loading that revolves around proper sizing and consistent seating depth.

 

[AlNyhus]

My presses are all loose enough to let the die do it's job. A rubber 'o' ring under the die lock ring allows some additional flex in the system.

 

[wkdickinson]

"Loose" (self-aligning) is why the Forster COAX works so well.

 

[Emmett Dibble]

A press has but a few basic functions.

Number one is it furnishes the power to insert and remove the case from the die.

The dies have the specific function of sizing the case properly and insuring consistent seating depth.

Number Two is during this function, the press must allow the dies to do their job with the least amount of interference as possible.

Be willing to check your loaded rounds. Arrive at a number you can live with, and see if your equipment is meeting this standard.

I have read information in threads where shooters have bought the best of everything, and still found runnout in loaded rounds. Usually in the neighborhood of .003 tp .005 inch.

The discussion then drifts into “does that amount of runnout really matter”?

It sure doesn’t help. But does it really show up on the target?

However, .003 to .005 variation in seating depth does matter in extreme accuracy shooting.

So concentrate on the aspects of loading that revolves around proper sizing and consistent seating depth.

Well said. I'm lazy by nature and have a minimum acceptable level of accuracy that I require then only concentrate on the big things that get me to that point. Some people enjoy picking the fly poop out of the pepper, I'd rather go shoot.

(and there is NOTHING wrong with enjoying picking the fly poop out of the pepper, I am speaking for myself only)

 

[NZ_Fclass]

Reloading is the best of times and the worst of times.

I can make really good ammo. Cleaned, annealed, measured, sized, filled correctly - to .01g, after careful testing, correct tension, bullet seated to exact length, shiny, packed. I have done my part.

Now I have to make 99 more.

Thank goodness that I no longer have to use a single stage press, a beam scale or a yellow Lee cup on a stick, a hand primer...and with some of the newer, albeit costly, gear, I can make those 99 identical to the first and still enjoy the process. And I'm not knocking those that have the patience to load any other way.

 

[K22]

This is a subject that is near and dear to my heart. For the vast majority of my reloading I use a cheap RCBS Partner press. The one thing that was done to it is the top of the press was squared up to play nice with the die. A creative gunsmith I know does this work to Partner presses. This press itself couldn’t be any sloppier in operation but that’s not a bad thing. It’s reloaded many thousands of BR quality rounds

In case you can’t tell, I’m firmly in the camp that believes the die does the actual work to the brass and the press is just the means to that end. A sloppy ram and a nice squared up die is hard to beat. Don’t believe that? Go to a short range BR match and you may be surprised how many Partner presses you still see in use. If they weren’t capable of making good ammo, they wouldn’t exist in that arena.

Presses are just another thing us reloading types tend to obsess over to create solutions to problems that most likely don’t exist. It’s easy enough to verify the end result by the brass that comes out of the die at the end of the sizing operation.

I have an RCBC Jr., circa 1970, seems to still be working just fine after loading literally thousands of rifle and pistol rounds - just ask the varmints / predators in my area. Oops - that was dumb - you can't ask them - they went to their final reward.

Creating solutions to problems that don't exist is a favorite endeavor on the internet - just surf the net for the gun cleaning videos.

However, we must never forget, it's a hobby, so if you enjoy tinkering with your press - go for it. I do believe mounting your press securely to a sturdy bench so there is no flex when you size a case is beneficial, but I can't prove it.

 

[jimmymac]

However, we must never forget, it's a hobby, so if you enjoy tinkering with your press - go for it. I do believe mounting your press securely to a sturdy bench so there is no flex when you size a case is beneficial, but I can't prove it.

You are correct. I’m guilty of not remembering it’s a hobby. Everyone reloads for different reasons. For me, reloading doesn’t feel like a hobby so much. My hobby is shooting BR. I just happen to have to reload in order to do that so it’s more work like for me but not quite. It’s a task I have to do kind of like mowing the lawn. I don’t mind mowing, but I’d rather be fishing.

For several years now, my focus has been on reloading more efficiently to get through the task as fast as possible while maintaining high quality control. So maybe reloading is a hobby for me then, but I’m coming at it from a different angle as I continue to streamline my processes.

You have given me some stuff to think about. Maybe I ought to sell all this shit and just go fishing. Nah!

 

[nmkid]

The best mods I have done to my Rock-chucker Supreme is pictured here. First of all I went thru it and tightened up the linkage to reduce the play. Then as seen in the pic I shimmed the front of it to make sure it was sitting level on the bench. Front to back and side to side. Lastly, I removed the spring clip from the ram and replaced it with a proper-sized O-ring to hold the shell holder in place. I placed a small magnet behind the ram to assure the shell holder was retracted back to center each time I remove a case.

Gotta do that magnet thingy.

 

[Tesoro]

Sell all green and go red. ( bonanza/forster) !!

 

[Dave M.]

Like any machined collection of parts, especially the mass produced ones, no press is perfect. I’ve been guilty of assuming my rock chucker is just fine, but it’s time to go through it, case holders, dies, even the primer seater stem. What have you guys checked and what was the most surprising? What did you do about it?

Is the end of the ram square and flat? Heck, is the ram even straight? How much slop in the ram is ok? Is the shell holder centered on the threads for the dies? Are those threads straight? Is the bearing surface true to the bore and flat? How true is the interior to the exterior to the bearing surface of the nut?

Which of the major makers has the best machining?

Wasting your time. Quality ammo comes from clean, quality dies. I’ve won three state championships using the same Hornady Lock n Load classic press that I bought 15+ years ago.