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45-70 Chevroner
03-17-2010, 09:33 AM
Lee does not make a factory crimp die for the 7MMTCU and I was wondering if one of the other 7MM factory crimp dies would work or is it necessary to crimp
at all as they are being shot in a single shot ie. 14" TC? I am trying a new load (to me).. It is20grs. H4198 for about 1850 to 190FPS with a RCBS 145gr. Sil. boolit water dropped WW with a little tin.

GrizzLeeBear
03-17-2010, 01:03 PM
I used to shoot a 7mmTCU for sillywets, your load should work just fine without a crimp. Most bottleneck calibers work fine with no crimp. Sometimes a crimp will improve the burning characteristics of a given powder, or accuracy of a given load etc., but a lot of times it makes no difference at all. Try it without the crimp. If it shoots well, you're done.

Kraschenbirn
03-17-2010, 01:46 PM
+1 on "no crimp" for your 7 TCUs. Back in the '80s, I used a 135 gr. Lyman 287221 Loverin (wish I still owned that mould!) from a 10" TC. At around 1450-1500 fps, boolits were perfectly adequate for chickens and pigs.

Bill

fredj338
03-17-2010, 03:13 PM
I've not used lead bullets in mine, but never crimped. The issue would be if you use an M type die to bell the case, then you would want to at least remove the bell.

45-70 Chevroner
03-17-2010, 08:46 PM
Thanks guys. The answer was what I was looking for I have a hundred loaded up and was just waiting for some input. I like the idea of no crimp and yes I have the seater die adjusted to remove the bell.

45-70 Chevroner
03-18-2010, 05:21 PM
I went out today and shot some of the aforementioned loads. Lousy groups but the wind was doing about 25+. Conditions could have been better but even at 25yds it would just stay on a 9x11 target sheet. I seated the Boolit to touch the lands and did all the little tricks ie. weighed the powder the bullets etc. After about 15 or 20 shots I could hardly get a round to chamber. Will a short chamber cause erratic groups. The pistol was hard to close also. I just got this bbl in a trade and it is the only one I have that is hard to close on a loaded round. Yes the cases are trimed to the proper length.

stubshaft
03-18-2010, 06:05 PM
My standard load for the TCU was/is 25.5gr 322 behind the 145 RCBS boolit. I shot this in Standing and Production for many years.

Shuz
03-18-2010, 09:24 PM
I shot the 7mmTCU for many years in IHMSA competition with the 070 Saeco boolit and H-322 and never saw the need to crimp. Guns used were both a T/C 10" and a Rem XP-100.

HORNET
03-19-2010, 08:11 AM
Contenders can be a little finicky about headspacing and lockup. I've usually had to seat boolits just off contact and adjust the sizing die to where it just closes with very light resistance on a case. You can probably find more details down in the handcannons forum or a link to Bellm's Contender site.

45-70 Chevroner
03-19-2010, 11:06 AM
Hornet: Tried both sites can't find them. What is the actual web site name?

high standard 40
03-19-2010, 12:40 PM
Mike Bellm's site.

http://www.bellmtcs.com/store/

HORNET
03-19-2010, 01:05 PM
Thanks, HS40, I didn't remember quite what it was and then got distracted.
As far as the handcannon forum, it's down the main index page as 'Wheelguns, Pistols, and Handcannons" or: http://castboolits.gunloads.com/forumdisplay.php?f=14 and search around or ask questions. You might even find some info in the Single Shots forum. Bellm's site is pretty good, though, lots of info.

buckweet
03-27-2010, 04:07 AM
but ? still no answer... can you use a lee 7mm crimp die from a 7-waters ? or something like that ?

anyone know of a crimp die ? for the 7mmtcu ?

thanks.


weet

357maximum
03-27-2010, 06:02 AM
weet

The point is "YOU DO NOT GENERALLY NEED NOR WANT THAT CRIMP DIE........ FOR OUR USES ESPECIALLY". Heck on my toys that do not "need to feed" I generally do not remove all of the bell...........self centering that way especially with short light for caliber cast......works real well for me.

243winxb
03-27-2010, 09:06 AM
Dont seat Boolit to touch the lands.
yes I have the seater die adjusted to remove the bell. Leave the bell (Lyman "M"die) in if the empty brass will chamber, this will help center the round in the chamber. No crimp. Adjust your cartridge headspace so the action closes as if no round is in the chamber. Cast bullets should be .002" larger the groove diameter. Oven heat treat your boolits, and water drop, works a whole lot better than droping from the mould. Mine split necks a lot.

buckweet
03-27-2010, 11:00 AM
lol !!!! but i still want to crimp em !!!!!

im tyring to gets a savage model 11, swapped over to the 7mmtcu, bolt action.

i understand, with my contenders, but ? still even then ? i'ed like to try crimping them.

weet

243winxb
03-27-2010, 11:23 AM
but ? still no answer... can you use a lee 7mm crimp die from a 7-waters ? or something like that ?

anyone know of a crimp die ? for the 7mmtcu ?

thanks.


weet Look here http://www.leeprecision.com/cgi/faq/index.cgi or email Lee, address available @ bottom of link page. [smilie=w:
Interchanging Factory Crimp Dies

Factory Crimp Dies are cartridge specific. The only way in which one caliber can be used for another is if the two calibers share bullet dieameter and trim length exactly. Factory Crimp dies generally use about .050 of the case to apply the crimp so any difference in the trim length between the cartridges comes off that amount.

buckweet
03-27-2010, 05:27 PM
thanks !!! and for the link !!!!

quilbilly
03-28-2010, 12:35 AM
I have both a 10" bl Contender and and 20" barrel Contender carbine in 7tcu and have not found crimping necessary in either to get fine accuracy. I enjoy the carbine so much that I hope to bring it to the Nevada shoot in May.