Forster co-ax press question...

[JAnderson94]

I used a RCBS hand primer for a long time. Switched to my Co-Ax a little while ago. When I made the switch I started to uniform primer pockets. I also switched to using thrown charges with a lyman 55. My cheap AR will shoot 20 shot 3/4' groups consistently all day long, close to 3/8" with 5 shots. Makes me think that I'm doing something right with the primers.

 

[1shot]

Consistent ignition is one of the steps to an accurate load.
Lloyd

 

[copperking81]

Ok, reporting back after tinkering with this some more today. I looked at the jaws and I don't see any issues with them (i.e. too sharp, burrs, etc). I ran some more brass through the primer applying minimal force and still, I get the marring on the rim.

Here's the only thing I can come up with. The brass I'm priming is .204 Ruger. The gap between the rim and case body is pretty small and not very deep. I don't think the jaws are getting an evenly distributed grip on the rim and when pressure is applied, the jaws are digging into the edges of the rim. The case as a whole is small and I'm wondering if this simply isn't a good design for small cases like this...thoughts or experiences to the contrary anyone?

Right now all I have on hand are small rifle primers and only use those for my .204 Ruger. Haven't gotten ahold of larger rifle primers yet so can't see if I get the same effect on larger casings.

 

[copperking81]

I agree with savagedasher in that the seating has always been very consistent. In fact, I think that I read somewhere (probably in some Forster literature) that the system is set up so as not to overpressure the seating and you get the same seat every time-given that I routinely forget where I left my eyeglasses please take this with a large dose of salt.
Anyway, when I do small runs of reloads that need to be of the highest precision I can muster, I will use the built in seater on the press-yeah, it takes longer than the hand press but I like what it produces so I stay with it.

I will also assume that the OP is using the handydandy little double ended plug that they provide to initially set up the primer seater-yes you can eyeball it but why?

I have yet to bugger up a rim on the press primer but there is still time

Gary

Yep, I'm using the plug but that doesn't seem to really help. Every time I use it to prep the system for the .204 Ruger brass, I end up having to tighten the jaws past what the plug calibrated it to. Hopefully that works better on larger brass.

 

[ballison]

The jaws on the primer seater can be reversed for different size case rims. You might want to try this.

 

[copperking81]

The jaws on the primer seater can be reversed for different size case rims. You might want to try this.

Tried that. Same effect.

 

[savagedasher]

Tried that. Same effect.

Sound like a miss alignment to me . Larry

 

[copperking81]

I tried running some larger brass through it tonight and no problem at all. All the brass came out just fine with no marring from the jaws. I think it has to do with the smaller .204 brass.

I'll probably call Forster and see what they recommend.

 

[savagedasher]

I tried running some larger brass through it tonight and no problem at all. All the brass came out just fine with no marring from the jaws. I think it has to do with the smaller .204 brass.

I'll probably call Forster and see what they recommend.

Great idea. Larry

 

[msinc]

If the impressions cause a problem, try using less pressure to seat the primers and see if that works. Personally, I went the hand priming tool route, as I was having inconsistent ignition when I used less pressure. Takes about the same amount of time, and hand priming is nearly foolproof. Not saying the priming portion of the press was less than desirable, it could be a case of me not being as smart as the press.

Would you please be so kind as to expand on just how you knew you were having inconsistent ignition???? Thanks in advance.

 

[jimcasey01]

Would you please be so kind as to expand on just how you knew you were having inconsistent ignition???? Thanks in advance.

I had a number of rounds not fire, mixed with some that did. Primer pockets had been uniformed prior to getting the press. I played with the press to no avail. This was a new experience to me, so I assumed it was me. I attempted to correct the problem, but with my lack of coordination and youth, I had trouble "feeling" the primers seat and gave up on it. Using the same primers, same lot, same box, I had no fail to fire with hand priming. Other than for priming, I am very satisfied with the press.

 

[Cecil S.]

Please pass the popcorn. LOL

 

[M-61]

OP QUOTE ".....I'll probably call Forster and see what they recommend....."

That would be my first step.

 

[6MT]

I used an RCBS hand primer for a long time until .338LM cases wore out the arm. I tried my coax primer. Once you get the hang of it and realize the mechanical advantage of the arm, it's just like a hot knife through butter. Silky smooth and perfect seating every time. Is it as fast as a hand unit? Nope. But I'll never go back. Even for .223 cases.

My 2 cents for what it's worth.