Factory rifle crimps?

[coop2564]

Got a lee factory crimper, put a medium crimp on, started working up on charge and started seeing pressure sign 1.5 grs sooner than I did without the crimp! Using 6.5 cm Hornady cases, 142 ABLR RL26 without crimp no pressure signs at 48gr 2840fps.
With crimp 46.5 had flat and flowed primer dimple. 47 hard bolt lift and same primer. My chrono is at deer camp 6hrs away so no speed check yet. Had some of my 48gr loads it shot them just fine! Anyone had anything similar happen when crimping?

 

[SilverbulletMAG]

First few times I used it I had the same findings. Pressure way too early and was giving a much tighter crimp than I realized. That's my only real gripe with the lee factory crimp die......directions aren't great and it's very hard to get a consistent crimp. What may be a medium crimp to one guy is a heavy crimp to another. If you follow the directions, most likely it's a heavy crimp.

I started placing the bullet in the press and running that to the top without the crimp die in. With the bullet at the top, then lower the crimp die until I can't screw it down any more by hand. I then get a reference point off the die and give it between 1/4 or 1/2 turn more. I don't go any more than a half turn from first contact with the bullet.
This isn't what the directions call for but has worked much better for me. When I went based off the directions, I was getting way to much crimp and pressure signs early, as you found. Light crimp overall has given me the best results and more consistency in the process.

 

[xsn10s]

I had excellent results with the Lee Factory Crimp. But that was with new brass, I haven't used it on once fired yet. Maybe it works best on annealed and FL resized?

 

[coop2564]

First few times I used it I had the same findings. Pressure way too early and was giving a much tighter crimp than I realized. That's my only real gripe with the lee factory crimp die......directions aren't great and it's very hard to get a consistent crimp. What may be a medium crimp to one guy is a heavy crimp to another. If you follow the directions, most likely it's a heavy crimp.

I started placing the bullet in the press and running that to the top without the crimp die in. With the bullet at the top, then lower the crimp die until I can't screw it down any more by hand. I then get a reference point off the die and give it between 1/4 or 1/2 turn more. I don't go any more than a half turn from first contact with the bullet.
This isn't what the directions call for but has worked much better for me. When I went based off the directions, I was getting way to much crimp and pressure signs early, as you found. Light crimp overall has given me the best results and more consistency in the process.

I did same thing and 1/2 turn. Can definitely feel it squeezing some. Ill back off a slight amount. I expected increased pressure since bullet would hold slightly longer but not quite that much.

 

[bigedp51]

Whidden custom dies sells expander kits with 5 expanders from bullet diameter to .004 under bullet diameter.

Meaning you can increase bullet grip with a smaller expander and not crimp the bullet.

Example below, many AR15 shooters use the Lyman type "M" expander with .003 bullet grip. The case mouth is bumped onto the .226 section to aid straight inline bullet seating. And "IF" needed a very slight taper crimp can be applied to the case mouth. I also use the same method with my 30-30 reloads with a slight taper crimp.

NOTE, RCBS AR-Series dies are taper crimp dies and used to streamline the case mouth for feeding

 

[243winxb]

Sometimes you can have to much of a good thing..

 

[RT2506]

I use the Lee Factory Crimp on all my semi auto loads and on the old military rifles I shoot that most have throats a mile long. I get better accuracy with the crimp than without from my vast experimenting. This is how I set up my die to get what I call a medium crimp that I have found works best for me no matter what the caliber or rifle it is used in. I put the shell holder in the ram and raise the ram with out using a round, just use the shell holder. I then screw the crimping die down while looking into the top of the die watching the crimping fingers. When they start to close up I stop half way between full open and full closed. I replace the Lee locking ring with one that can be locked down with a set screw this way I can repeat my crimp when I remove and replace the crimping die in the press.

 

[coop2564]

Backed off 1/8 of turn made a big difference! No pressure signs at 47.5 tho a little tight bolt at 48. Factory type crimping will affect your pressure if anyone has thoughts of trying it!

 

[SilverbulletMAG]

How'd you're groups look?

 

[coop2564]

Not outstanding but not bad most where in .75 moa range. Best .55 now ive got to go in march for turkey hunt and get my chrono to see speed and fine tune it!

 

[jwing]

They they work great. I use in auto guns. And compressed loads 6.5 grendel.

1 st necks need to be turned consistent.
Seat a bullet get a reading then use your collet die slowly and testing to you get 1/2 th shoot then go 1 th test so on.. you guy need enough to keep pulled from moving. 1 thousand is a lot.