.404J Factory Crimp Die - Possible to modify .416 Rigby FCD?

[deewayne2003]

With Lee being out of the custom die game for an undetermined amount of time; I am wondering if it would be possible to have a machine shop modify an existing .416 Rigby factory crimp die?

Can someone on the forum with machining experience tell me if I'm onto something and how difficult/expensive would it be to modify this die to .404J?

As I see it the .416Rigby is larger in every dimension....oddly enough except for the projectile & neck.

So would it be as simple as ....

Shortening the die body or machining a spacer to make the difference between 2.8748 & 2.9000 (.0252"); and then opening up the 'crimp petals' .007" to accept the larger projectile?

This is a Lee Factory Crimp die in .416 Rigby

.416 Rigby

.404J

P.S. - I'll be impressed if we can keep this thread on track and answer the question at hand without someone throwing in their opinion on crimping merits or how they use their (insert opinion/method) instead of answering the question.

 

[Razorback]

That would be interesting to know. I can tell you a 416 rem FCD doesn’t work unmodified. I thought about reaming it out.

 

[deewayne2003]

That would be interesting to know. I can tell you a 416 rem FCD doesn’t work unmodified. I thought about reaming it out.

The .416Rem is too short by .0248" if I'm not mistaken; so reaming it out would just destroy the die.

 

[457121]

The collet is the issue. In the machine shop world there is tooling called emergency collets. This is a 3 slit collet with a 1/16" pilot hole and is not hardened so you can bore it to your desired size/shape. The Lee collet is a 4 slit design. I don't have a .404 Jeffrey dummy round or shell holder to use as an example.

 

[deewayne2003]

The collet is the issue. In the machine shop world there are tooling called emergency collets. This is a 3 slit collet with a 1/16" pilot hole and is not hardened so you can bore it to your desired size/shape. The Lee collet is a 4 slit design.

So you are saying that it is an issue with the tooling it would take to machine the 4 slit system vs the standard 3 slit?

 

[457121]

So you are saying that it is an issue with the tooling it would take to machine the 4 slit system vs the standard 3 slit?

Well it would be a little easier if I could adapt a pre-made collet to the Lee die body rather than start from scratch to keep the price reasonable.

 

[deewayne2003]

Well it would be a little easier if I could adapt a pre-made collet to the Lee die body rather than start from scratch to keep the price reasonable.

You say start from scratch... I'm talking about machining the existing collet in the die; trying to make sure we are on the same page but your brief postings are open ended.

 

[457121]

Sorry about being unclear. Trying to machine an existing collet of a .416 Rem (for example) FCD would be difficult because the collet finger are thin and springy. You would have to build some fixture to support the fingers and hold the body. It would be easier to build a new collet to correct diamentions then slit the collet body and install in an existing outer Lee die body. I was trying to think of a way to build this with using some existing parts to keep price down instead of building the collet and the body from scratch.

 

[deewayne2003]

Understood... do you think that it would be possible to use the die as is, but with the spacer to get the length correct and setting die to minimum crimp seeing as the projectile difference of diameter is .007"?

 

[457121]

Understood... do you think that it would be possible to use the die as is, but with the spacer to get the length correct and setting die to minimum crimp seeing as the projectile difference of diameter is .007"?

It just might work. Most collects in the machine shop arena have about a + or - tolerance of around .008" to .010". I did modify a 6.5x55 Swede FCD once to work on the 6.5x54 M-S by turning down the overall length of the collet by .055" (material removed from the bottom of collet where they stamp the caliber) to fit the shorter M-S case. This was before someone contracted Lee to make a run for the M-S. Now I'm just going to think out loud so to speak but might be wrong because I don't have a .404 dummy round or a .416 Rigby FCD to look at and compare. If you can fit the .404 into the Rigby die and there is enough clearance to get the case neck where it needs to be then all you would have to do is shave the .025" off the bottom of the collet.

 

[457121]

Another idea, (if the .404 slips into the Rigby FCD) is if you need to open the finger end of the Rigby collet, would be to wrap a 3/8" steel rod with a narrow strip of 220 grit sand paper where the neck would be and screw the die down until it just kisses the sand paper and turn the rod while hold the paper. When it feels like it is getting loose screw it down some more and start turning again until it has the proper clearance.

 

[deewayne2003]

It just might work. Most collects in the machine shop arena have about a + or - tolerance of around .008" to .010". I did modify a 6.5x55 Swede FCD once to work on the 6.5x54 M-S by turning down the overall length of the collet by .055" (material removed from the bottom of collet where they stamp the caliber) to fit the shorter M-S case. This was before someone contracted Lee to make a run for the M-S. Now I'm just going to think out loud so to speak but might be wrong because I don't have a .404 dummy round or a .416 Rigby FCD to look at and compare. If you can fit the .404 into the Rigby die and there is enough clearance to get the case neck where it needs to be then all you would have to do is shave the .025" off the bottom of the collet.

I think Shaving down the length of the collet to accept the shorter .404J.... I could easily answer this if I hadn't sent off my .404J dummy rounds with the rifle for conversion feed testing.

However I am supposed to have .404J cases, dies and bullets inbound; if the backlog of mail and packages from the "Texas Blizzard" ever catches up! - For those of you wondering, there were not people being hunted by Polar Bears on 6th St. as CNN news would have you believe; it was 9F last Tuesday in Austin, and Today it was 78F!

Back to the subject at hand... I would be willing to risk my .416 Rigby FCD if a qualified person with the correct tools for the job is up to it and we can work out a deal.

457121.... perhaps put your head together with fourfive8 from the OP searching for such dies thread; after all if it works I think there would be several people from this forum alone interested in the modification service, and I think that would be 100% legal to modify an existing product vs. trying to copy the patented design as some people have suggested?

https://www.africahunting.com/threa...imp-die-want-to-buy-or-even-rent.61457/page-3

 

[Scrumbag]

Interesting stuff!

 

[Adam From Africa]

I use a 416 Remington FCD to crimp my Rigby rounds. Insert from the top through a spacer and crimp away.

 

[Adam From Africa]

 

[Adam From Africa]

Adjusting the crimp force is just a matter of turning the die further in or out where it meets the rising ram. Should work for a 404 J also.

 

[cmk]

I use a 416 Remington FCD to crimp my Rigby rounds. Insert from the top through a spacer and crimp away.

Oh lord... this is such an ingenious solution! So simple, and yet so clever, and I never even thought about it!

I've been trying to think of ways to crimp the 404J, without having to deal with the 'large die' problem, i.e. having to remove/insert the 1,25" to 7/8" bushing all the time..

I'd love to know the size of the opening of any .416 FCD when it is not under tension, i.e. would it be possible to fit a 404J neck into it, without any sanding/grinding/honing. Wouldn't matter if is almost zero clearance, as I believe the die could be turned out until a full pull on the handle juuuuust kisses the die and gives enough crimp.

A quick check on some rounds says that .450" is the absolute minimum needed. .455" or - even better - .460", would be perfect, as that would also handle cartridges loaded cast bullets (which run att .425" instead of .423")

EDIT: Come to think of it, perhaps a LARGER FCD would work as well, e.g. for the 44-40 (.427" bullets) or .44 Magnum (.429" bullets), but I guess it depends how much crimp they actually allow for. If anyone has one of these dies and could take a measurement of the inner diameter of the collet when fully closed, I'd much appreciate it.

 

[John458Lott]

With Lee being out of the custom die game for an undetermined amount of time; I am wondering if it would be possible to have a machine shop modify an existing .416 Rigby factory crimp die?

Can someone on the forum with machining experience tell me if I'm onto something and how difficult/expensive would it be to modify this die to .404J?

As I see it the .416Rigby is larger in every dimension....oddly enough except for the projectile & neck.

So would it be as simple as ....

Shortening the die body or machining a spacer to make the difference between 2.8748 & 2.9000 (.0252"); and then opening up the 'crimp petals' .007" to accept the larger projectile?

This is a Lee Factory Crimp die in .416 Rigby
View attachment 390216View attachment 390217View attachment 390220

.416 Rigby
View attachment 390218
.404J
View attachment 390219

P.S. - I'll be impressed if we can keep this thread on track and answer the question at hand without someone throwing in their opinion on crimping merits or how they use their (insert opinion/method) instead of answering the question.

I just use the 416 Rem factory crimp die and it works just fine for my 404 Jeffery rounds. I posted the pictures on another thread. The Rigby FCD looks the same as the 416 Rem on btw.