7mm TCU from 223 Remington

[Leadmelter]

I thought I read somewhere you could fire a 223 Remington in a TC Contender barrel to form it to 7mm TCU with minimum brass loss?
True Fact

Leadmelter

[NSB]

That's a fact. I shot the 7tcu for silhouette for several years and all I did was put the .223 in the gun, point it at the berm, and pull the trigger. Perfectly formed brass. I still have a lot of it sitting around and haven't had a 7tcu for about fifteen years. Fire away.

[garandsrus]

You can expand once fired .223 brass also. I don't think I lost many cases.

[kenyerian]

http://specialtypistols.infopop.cc/eve/forums/a/tpc/f/6676017655/m/5211067824/r/?f=6676017655&a=tpc&m=5211067824&s=9066056864 Very good step by step article on this in the Specialty Pistol Forums. You do have to be a member to view it. I've noticed that several members on this forum also post on Specialty pistols. I have an a 6mm die set I expand with first than use the 7TCU. I have also just fired 223's in the 7Tcu as well. Both work but I like to start with new brass.

[6.5 mike]

I've been using the 130 gr lee pp'ed with a starting load of imr4198 to fire form my brass since I got my bbl. So far has worked very well. The 7 m/m soup can works good also.

[high standard 40]

I have 3 different 7TCU handguns and have fired many thousands of rounds in silhouette matches. The TCU is one of the easiest cases to form that I have encountered. I have a tapered expander in my FL die and it takes one simple pass in this die to form my cases. I then just load them with my normal charge and bullet. I have found there is no need to "fire form" them first. I've shot many perfect scores with brass that was not "fire formed" first and so have many other shooters. Depending on the brass you start with, you may want to anneal the case mouth first to reduce losses due to neck splits while forming. I skip this step because I have buckets full of 223 brass and can stand an occasional lost case.

In response to your original question. I never formed 7TCU brass by firing a loaded 223 cartridge. I feel it is a waste of components.

[KLR]

it takes one simple pass in this die to form my cases.

In response to your original question. I never formed 7TCU brass by firing a loaded 223 cartridge. I feel it is a waste of components.

Ditto.

I have a set of RCBS dies. I don't know what style of expander it has, but it forms 7TCU from 223 in one pass. Just be sure to lube the inside of the case neck well.

I'm using this die as the first step to forming 30-223. I haven't split a neck yet with the 7TCU die.

[coyotewacker]

I used cream of wheat and bullseye back in the early 80's

[donald duck]

Maybe I do it the Hard Way, but I once had a .257 JDJ barrel and dies. While I had the dies I opened several .223 cases to .25, then opened them to .285. Loaded and fire formed with 120 grain cast bullet with gas check. Never seem to lose cases. Now have a .257 or .25 TCU and love it. Have a Shilen 7 MM TCU Barrel on my Savage Axis and it is a tack driver. Never a need to load hot loads with cast bullets. can now shoot them at about the same cost as .22 long rifle. dd

[Ohio3Wheels]

Have both the 7mm TCU and the 6.5mm TCU, I did the 223 or 5.56 thing back when cheap ammo was available, but I also FL sized new or once fired and shot matches with my fire forming loads. Same load I used in formed cases. It all worked okay.

Curt

[buckweet]

How long does you guys brass last ?

[high standard 40]

I have some that have been fired 12 times with no lost cases. Then I've had some lots of brass that split with the first firing. Recent lots of 223 brass are not properly annealed, in my opinion. So it's a roll of the dice what your results will be.

[marshall623]

The first batch of 7TCU brass I run was from 1x fired RP and I have had at least 10-15 loadings before I started loosing cases . I’m working with a batch of Mil spec now , I have to tweak some loads a bit . From what I can tell once they are fire formed , it looks like the Mil spec is going to last a while also . My TCU only sees cast and no max loads , just what shoots good .

[Three44s]

I have not worked with 7 mm TCU since I got myself a used Redding bushing die a few years ago but I suspect there is no better way to control neck working. I do have to figure what bushing I need because it came to me “naked”.

Also I have been drooling over the DIY semi automated brass annealers.

I was losing an unacceptable number of cases when I was converting in the near past. My first foray was fine but the later run was not pretty.

I have a safety net of sorts for buggered .223/5.56 however: 222 Rem and lastly 7.62X25 mm

Three44s

[gnappi]

Back in the day, I also fire formed them.