A �cam over� is when the shelholder and the die touch just before the handle is bottomed out and you get a slight compression and the�clunk� or whatever you want to call it that supposed to take the flexing of the press which again is impossible to get unless the shellholder and the die touch. This cam over is Normally associated with FL sizing dies NOT ON seating dies.
On a seating die you bottom out the handle raising the press to its highest and adjust your seating die per manufacturer instructions but there should be no cam over felt.
Seating dies like Whidden and Forster push a sleeve up but there is not enough resistance to get a cam over effect.... unless y�all�s definition of cam over is totally different than mine?
In general camover is not a good thing as it�s stresses the press. One reason I like Whidden dies as they will fully size your brass while never touching the shellholder.

Yeah cam over was not a good choice of words...I new someone that used it in the since of a fully extended stroked as opposed to a crimp stroke which is not fully extended

But a oal issue would most l likely not be caused the press but rather the die and stroke. The only two issues I could say causing the press to cause the issue is the c press as someone pointed out above. But seating should have very little force involved so it shouldn�t move the press that much or else resizing would be way odd. Or the die threading is off which you should be able to feel.

I'm not understanding correctly. Some are saying yes, definitely cam over while seating while others are saying what printed instructions advise which is to leave space between shell holder and die. I can't see how both could be possible.

^^That is cam over.

Often needed to get a full length size on brass. Stepson's AR-15 needs this. I set up his die by screwing it down to touch the ram. Raised the ram, and trial and error until what felt like cam over to me. It equated to a little more than another 1/4 turn.

Are we talking about compressed powder loads and what is the inside of the diameter of the neck in relation to the bullet diameter? I have seen more than one bullet creep a little with compressed loads.

I doubt that your seating depth issue is press related. What type bullets and what brand of seater die along with the question are they compressed loads are all more likely places to look. Example if you are using ELD type bullets they need a special seating stem or you get inconsistent depths.

I found that the ram has a good bit of play in it when up. Can't say that is the problem but can't say it isn't. Lets face it, I have the cheapest press money can buy and I'm going to replace it with a better one. The seater is Redding and bullets are ELD. Loads are not compressed. As for the special seating stem, I bought the die from Custom Reloads of Dallas after he worked up 2 loads for me. I honestly have no clue as to the stem. I have yet to read an answer to the question will the RCBS Chucker Supreme be better or load more precise ammo than the Partner. JG did point out that a pile of different dies might be a pain in the buttocks to change out but I don't load that much ammo for it to be an issue. As you can gather, I need the practice setting up anyway. I want to be able to do it repeatedly and repeatably.

I think all you'll get here is opinions. I happen to have one to offer: As far as seating goes, I believe the Partner will work every bit as well as the Rockchucker. You might find the Partner to be a bit light for full-length sizing stuff like .338 Lapua, but on run-of-the-mill .223, .308, and pistol cartridges should be a piece of cake. You have not declared that you're using the cheapest Lee press, but I'd assume that's what it is. Lots of Lee users get offended, but I'd replace that PDQ.

You won't go wrong with RCBS.

Never loaded on a partner but did do a test one time with several presses. The same die were used and ammo loaded on '

Herters press that outweighs the others combined
Lee Challenger Loads good ammo but is not as strong as the steel presses.
RCBS Rockchucker
Lyman Spar-T turret press.

Rifle used would shoot half MOA and could tell the difference in loads assembled on the first 3 presses but the Spar-T loaded ammo was less accurate. That is not surprising as the Spar-T is known to have some flex.

I now load mostly on a Coax press but to be honest I cannot tell in most of my rifles that it is any better than the first 3 presses listed above. The better leverage and no shell holders to replace is very nice along with the ease of changing dies.

As to the question of Partner of Rockchucker loading more ccurate ammo, the only way to know if try both presses. We can all speculate but that is exactly what we would be doing.

Either of the RCBS presses mentioned will load ammo just fine, but the Rock Chucker is much more robust. Put the two side by side and you can immediately tell the difference, and not just in the size. The Partner press is cast aluminum vs cast iron on the Rock Chucker. Everything about the Rock Chucker is much heavier duty from the frame to the ram and the cam linkage. Will the Rock Chucker shrink your groups in half? I doubt it. But for the marginal increase in price (the Rock Chucker can regularly be found in the $120 range), you�re getting a much better press. For what it�s worth, my main press is a Coax, but I�ve owned a Rock Chucker since I started reloading, and have loaded thousands of rounds on them.

Whoa. I didn't know RCBS made any press of aluminum. I'd spend the extra bucks on the Rockchucker and never look back in that case!

I have the RCBS Rock Chucker with Hornady dies and the stem for ELD bullets, and I don't get anywhere near 5 thousandths or more variation in seating depth. I measure with the Sinclair hex nut. My typical variation is plus or minus a thousandth, two at the worst. But I will disclaimer that with the statement that you're measuring very small amounts of difference with hand tools, and the propensity for error is significant if you're not being very consistent in your measurement methodology.

I've not used a Co-Ax, but I've heard nothing but good things about them. I use Hornady lock rings on all my dies and there is no extra setup time that I'm aware of - I just screw them down, run it once to measure whatever the result is and confirm that nothing has moved from last time, and then keep trucking. My biggest complaint, by far, is the primer catcher really sucks. I end up with primers everywhere, and even the ones it catches are hard to dispose of because the plastic tray thing is hard to get off without sending primers flying everywhere. I've got to where I don't even try to dump the primers - I just use a shop vac to suck all them out of the tray. Other than that, it's an awesome press.

This......Do you guys actually know how to reload...

If it was aluminum, I wouldn't recommend it either! This being a RCBS cast-iron press for $75 TYD, I don't see how you can lose. Definitely NOT a top-of-the-line press, but if you don't like it, sell it later & get most (if not all) of your money back. Like all RCBS s.stage presses, crappy spent primer handling. Other than that, GTG. With proper technique, it will load ammo as good as any other s.stage press.

Gary, if you are in the area anytime soon, come see me and I'll show you how I set up my bullet seating and FL sizing dies.

Chad, I will take you up on that at some point. Is the seating stem in that seating die you sold me the special ELD style? I went ahead and ordered the Rock Chucker Supreme and will use my Lee as a dedicated de-capper. The ram on that Lee has a lot of play and I can't trust it. I was unaware of this movement when I started this thread.

Pertnear, while I like to buy from Academy because they are a Texas company and they frequently deliver cheaper than others sell in store, the descriptions on some of their products is wrong. I have done some research and it turns out the older Partners were steel/iron but the newer ones are AL.

garyrapp55, thanks for the info. I hate to see RCBS cheapen-up, but I guess they have to compete with Lee.

BTW: I have the Hornady comparator with inserts & it has become something I use every time I load. If I was starting over I'd get the Sinclar Nut. I recently bought the anvil-attachment which I highly recommend. The only thing I don't like about it is the price. It is $16 for a small do-nothing disc of aluminum, but it sure is helpful in getting quick & accurate measurements. Should help when using the Hornady or Sinclair. Good Luck!

Yes, it's a Redding match grade die, and they seat the VLD style bullets well.

I think a better press is an excellent idea, no matter what, but one other thing that might make consistent seating depth difficult to impossible is hardened case necks. They can get to where they won't resize consistently and you might notice different feel during seating, from one round to the next. Annealing or new brass could be your answer, among other possibilities.

He's using brand new Lapua brass on this ammo he's loading.

I guess I missed that. Looks like that leaves the press itself, die setup, or measuring equipment or technique. What else is there??

Unless the primers aren't seated below flush.

RiverRider, I won't know what is causing this until I have a way to compare and eliminate possibilities. Because of the play in the ram on my press and the fact that it is not a rigid press to begin with, I ordered a better one. If this doesn't cure the problem I will continue my quest. When you said, "measuring equipment or technique", I thought of the Sinclair hex nut I use to measure from case head to nut (which sits on the ogive). I wiggle the round with nut attached a little back and forth to make certain calipers are in position and ease off the pressure my thumb is applying to the caliper to get a good reading. You think I may be measuring wrong and if so, how? I'm going to borrow another caliper from the shop here at work to compare to mine. Thanks for your help.

Well, it sounds to me like you're on top of that one Gary. I suppose it could be the caliper itself, but if you're using it on other rounds without issue I suppose you could say that's not it. With my digital caliper, I can cause inconsistent readings by varying thumb pressure so I have to work it carefully. Some are better than others...I've considered upgrading my own but haven't moved on it. I would assume you've checked to be sure your primer seating is below flush.

Hopefully your new press will fix things up.

Gary, I loaded a bunch of ammo on an old CH & Tool die press when I first started loading ammo. The ram had some wiggle in it also. It loaded great ammo. However, I did have some bullet run out in it. If you have your seating die set up where the press cams over, and you make a full stroke up, you will be fine.

The first time loading a new die or caliber, I always set my seating die up in this manner. There are 2 main adjustments on a seating die- the die body and the seating stem. I will clean the die out first, then take the seating stem out or back it way off. I'll insert an empty piece of brass into the shell holder and raise the ram all the way to the top with the brass in it. I'll lower the die down (mainly the body of the die) until the shoulder of the case makes contact with the die. Once I find this, I will back the die out about a 1/2 turn or two, depending on which bullet and how long the bullet is. I do this step so I know where the inside shoulder of the die is so I am not making hard contact with the brass case. Some reloaders will insert their die too low and will be crushing or making hard contact with the brass. You want to avoid this.

Once I have the body of the die set, I will get my powder charge and charge a case, and get ready to seat a bullet. The body of the die is locked down, and the seating stem is backed way off. I will insert this ready to seat round into the press and raise the ram all the way up. I will check the seating of the bullet with multiple pumps of the ram going up and down while adjusting the seating stem down. The ram is going all the way up and making a full stroke, or camming over. I do this very quickly since I can see the bullet on each pump, or raising of the ram. Once I see I am in the area of where I want to bullet seated, I will start to take COAL and ogive measurements. If the seating of the bullet is too deep and I have lowered the seating stem down all the way, then I will unscrew the body of the die out more to make room for the ram to cam over. So it's a relationship between the die body and the seating stem to get it setup correctly with the ram camming over. Once you set it up right on your press, you should not need to make an adjustment to the die body again. Make small adjustments to the seating stem to dial in your proper COAL or ogive measurement.