45/70 roll or lfcd

[lastborn]

Which is better, the Lee factory crimp die or a roll crimp with cast boolits in the 45/70 and WHY please? I have read that with the LFCD that cast boolits do not straighten the brass back out and it is harder on your brass.[is this true] I tried to insert a rem.405 gr sp into a fired case and it would not go in and the case. I know everybody likes something different but 99% of you have WAY MORE experience at this than I do and that is why I am asking.
{shooting 1895 }
Thanks

[Casting Timmy]

I read somewhere about using the sizer, so I just take out the decapping assembly and then use my full length sizer to crimp down after I've seated the bullets. I like it better than the roll crimp, but I've never used the LFCD so I can't really give you a comparison.

[iron mule]

lastborn
the crimp that you would want to use would depend on the type of firearm that you would be using
example a single shot would not require a roll crimp // i use what many call bullet-case tension which simply means the bullet fits tightly in the case the amount of tension varies on what the firearm like
with a firearm that has a tube magazine you would want to use a rol crimp to prevent bullet set back on the rounds in the magazine caused from recoil when the firearm is fired
so it depends on the firearm used
hope this help and that you have a good holiday season
mule

[Larry Gibson]

I read somewhere about using the sizer, so I just take out the decapping assembly and then use my full length sizer to crimp down after I've seated the bullets. I like it better than the roll crimp, but I've never used the LFCD so I can't really give you a comparison.

This what I do with my target loads for my target trapdoor. I also use this for my light 270 gr bullet loads over 8 gr Bullseye for 1050 fps and the 210 gr HB bullet over 6 gr Bullseye.

I use a Lee die that roll crimps for my m1873 cartridge replication loads using the 405 gr HB M1873 bullet or the 500 gr M1882 bullet. I got the Lee dies specifically made for the 45-70 BP loads from Wolf as per his instructions in his excellent book.

I use the LFCD on my 45-70 (450-400-70) loads using J bullets in my Siamese Mauser. These are very heavy recoiling loads (.458 Win Mag range) and require the heavy crimp. I use the Lee RC die for the heavy cast bullet loads for the Siamese Mauser. The lee C458-500-FN at 2050 fps really tests the crimp....so far so good:-)

Larry Gibson

[jlchucker]

The 45-70 loading that I do is for a Marlin 1895 bought new in 1982 or thereabouts. I started loading using an RCBS seating die to crimp. Later, when Lee came out with the Lee FCD I bought one and have been using it ever since. Either works well. I use it in all of the calibers that I crimp--including rimless ones like the 308 family. I don't do any more than just lightly "bump" the latter--I feel that it kind of makes tension at the case mouth more uniform case to case.

[rintinglen]

I prefer the Lee Factory crimp die simply because I don't have to trim my cases quite so carefully or often, and my 45-70 is a Marlin CB, so all rounds that are going through the magazine must be crimped pretty snuggly to avoid set back.

[onondaga]

I use both crimping methods but prefer the Lee Factory because it adjusts finely and independently of the bullet seating die in a separate step on my turret press. This allows me to check loaded cartridge length before crimping if I wish.. This is important to me because I can easily adjust seating depth and even pull bullets to correct error without worrying about the crimp damaging bullets.

[Frank]

Roll crimp is the best for accuracy in the 45-70. Too much crimp opens up groups bad in jacketed and cast.

[onondaga]

I don't see any reason for Franks reply. Never had type or amount crimp effect accuracy. Crimping prevents bullet set back from recoil with cartridges in magazines when firing and the crimp also aids propellant ignition by containing the charge longer after the primer goes off. That containment also effects the pressure curve and lowers the peak pressure while raising the start pressure resulting in a flatter curve. These physical effects have no reputation for decreasing accuracy. There is likely other factors causing Franks accuracy loss with heavy crimping. Crimp location on a lower edge of a bearing band can reduce the bearing band effect, but I've never seen that effect accuracy in 45/70 bullets with big multiple bands. Crimping on light bullets with a single bearing band would be questionable, but that is hardly the case with 45/70.

The recommendation from a Lee technical representative in a personal phone call with me was to measure the cartridge carefully after crimping in two locations. First measure diameter 1/8 inch back of the crimp then measure the crimp diameter at its minimum on the crimp itself. The difference should be .003 to .005 inches as recommended by Lee with .005 for lead bullets or the cannelure of jacketed bullets as a standard . One particular bullet manufacturer does advise against using the Lee factory crimp die to crimp not within the cannelure and claims that causes a pressure increase. The die is designed to work within that .005 inch specification but crimped cases can appear to have more crimp from the result of an over bore or worn overbore sizing die or under-sizing brass and also oversize bullets expanding cases. The technical representative also told me this is not mentioned in the instructions because it is an extreme anomaly for an over deep crimp to occur with the factory crimp die and the fault would lie with an out of specification sizing die or hard oversize bullets expanding brass resulting in an over crimped look as the crimp die will ignore the over expanded brass and crimp to design specification. I have never had any reason to question the reliability of the technical department at Lee and believe they are very scientific and helpful to customers.

Frank, kindly try to defend your statement with some facts of ballistic science to explain your position and convince us to believe you. Maximum crimping of soft bullets and consequently firing them with severely weak charges that are insufficient to expand the cartridge will cause bullet deformation of too soft bullets and effect accuracy but this is not the fault of the tools, this is common sense and and the fault of the person doing the loading ignoring physics and pushing below recommended standards. A very light/weak plinking load with a full crimp would be an example of that.

[onondaga]

lastborn
45/70 roll or lfcd
Which is better, the Lee factory crimp die or a roll crimp with cast boolits in the 45/70 and WHY please? I have read that with the LFCD that cast boolits do not straighten the brass back out and it is harder on your brass.[is this true] I tried to insert a rem.405 gr sp into a fired case and it would not go in and the case. I know everybody likes something different but 99% of you have WAY MORE experience at this than I do and that is why I am asking.
{shooting 1895 }

Lastborn:your bullet not inserting into a fired case is not a big problem and just indicates that your load had insufficient pressure to expand the case-mouth at the crimp upon firing. Normal case-mouth expansion before seating bullets will correct this. For cast bullets I use the Lee universal case-mouth expanding die the minimum amount adjustment that will allow the bullet to hand place within the case-mouth edge. If you have concern about this causing excessive brass hardening and subsequent case-mouth splitting then annealing after 8 of so loadings will remedy the problem and extend brass life.

[Frank]

Light crimp, 8-shot group, 100 yds, rifle, 45-70
http://castboolits.gunloads.com/picture.php?albumid=123&pictureid=2828

Light crimp, 5-shot group (left), 50 yds, handgun, 45-70
http://castboolits.gunloads.com/picture.php?albumid=123&pictureid=2884

A slower powder as used in the 45-70 doesn't have sufficient strength to overcome crimp variation. A light or no crimp has less variation

[bwarren86]

Which is better, the Lee factory crimp die or a roll crimp with cast boolits in the 45/70 and WHY please? I have read that with the LFCD that cast boolits do not straighten the brass back out and it is harder on your brass.[is this true] I tried to insert a rem.405 gr sp into a fired case and it would not go in and the case. I know everybody likes something different but 99% of you have WAY MORE experience at this than I do and that is why I am asking.
{shooting 1895 }
Thanks

I really like the lee factory crimp it does a simple good crimp