7-30 Waters and 7mm TCU early Contender handloads

[Bloodhound689]

Not sure if this should be in this area or case forming but I recently picked up two contenders (7-30 Waters and 7mm-TCU). This will be my first attempt at case/fire forming and have noticed both cases size just fine (using LC 5.56 and Win 30-30 cases). Both cases chamber and lock up fine prior to seating the bullet. Once I seat the bullet however the round does not chamber all the way and gets stuck. Doesn't matter how deep I seat the bullets. Almost like the bullet stretches the neck to much. I did not use any crimp on the bullets.

I read on here that you should start with the sizing die a couple turns out (which I did). After trying to chamber a round that would not chamber I ran the sizing die down to the shell holder then backed off a half turn or so. 2 of the 5 chambered. I am using RCBS dies. What are your thoughts?

I have been loading for a few years. Always learning though.

[daved63]

Are both calibers doing this? Did you measure the diameter of the neck once the bullet is seated? You should be able to measure and compare to the chamber specs to see if you are within tolerance.

[Bloodhound689]

Yes, both calibers. The necks measure .003-.005 bigger then the ones that do chamber. I didn't measure the bullets prior to seating though.

[Bloodhound689]

The bullets I am using are pulled 139g SP (brand unknown) from some reloaded rounds I received with the two contenders.

[725]

Different brass manufacturers may have different thickness of brass at the neck. I know my .38-55 needs Win brass for jacketed and Star brass for cast. If trying other headstamps doesn't fix the problem, you may have to neck turn your brass. Easy enough, but just one more step to do.

[Bloodhound689]

Good suggestion. I am usually picky about everything being the same headstamp but I am going to see what the others do

[Yooper003]

When I resized my 308 cases down to 7-08 ,I did neck turn to remove some stock. I got a simple hand turning rcbs mod. It works well.

[Bloodhound689]

I haven't loaded many bottleneck cartridges. Mainly handgun so neck turning is new to me as well. I'll order the tools.

[dk17hmr]

Are they factory TC barrels or aftermarket?

[Bloodhound689]

They are factory. 7mm-TCU 10" and 7-30 Waters is the Super 14

[daved63]

Yes, both calibers. The necks measure .003-.005 bigger then the ones that do chamber. I didn't measure the bullets prior to seating though.

What is the measurement on the ones that do not chamber? The SAAMI specs for the 7-30 Waters is 0.3062" at the end of the neck.

[BK7saum]

I am surprised that neither will chamber. Usually t/c chambers are generous. They should chamber reformed commercial brass. Not sure what the issue is. If you were applying a crimp, I would say that you had buckled the case necks.

[Bloodhound689]

They are measuring up at .3065.

[Bloodhound689]

If the case was buckled I would assume that they wouldn't chamber without the bullet as well. They don't appear to be buckled but then this is my first case forming. The double neck is different. Lol

[Bloodhound689]

Daved do you think a factory crimp die with no crimp would fix this .0003?


Corrected. Never mind. They are designed different for bottlenecks aren't they?

[dk17hmr]

Have you full length sized at all?

[daved63]

Looks like you will have to turn the necks or try a different brand of brass. I have formed quite a few 7-30 Waters and 7mm TCU cases and I don't recall ever having to turn the necks. Did you measure the bullets? I've shot cast bullets sized .285" in both of those cartridges and never had a problem. It seems strange that both would be doing it.

[daved63]

Daved do you think a factory crimp die with no crimp would fix this .0003?


Corrected. Never mind. They are designed different for bottlenecks aren't they?

One other thought since you are new to bottleneck reloading. How did you adjust the seater/crimper die? If it is over crimping it could bulge the case. Put an empty case in the shell holder and screw the die in until it touches the case mouth, then back the die out a half turn and lock it in place. Seat a bullet and see if you still see the same thing.

[Bloodhound689]

Have you full length sized at all?

Yes using RCBS dies

[Bloodhound689]

One other thought since you are new to bottleneck reloading. How did you adjust the seater/crimper die? If it is over crimping it could bulge the case. Put an empty case in the shell holder and screw the die in until it touches the case mouth, then back the die out a half turn and lock it in place. Seat a bullet and see if you still see the same thing.

I backed the die out a full turn

[Bloodhound689]

Well you all have given me a few options to try. I'm sure it's a combination of me being green on these rounds. Possibly the unknown pulled bullets. I am having a hard time finding new 7mm in the stores here. I will try some different brass and if that doesn't work. Order some tools to trim the necks

Thank you all

[daved63]

I backed the die out a full turn

Okay, I went and checked my reloads and measured the end of the case neck with the bullet in place. I got the following:
7mm TCU with Lee C285-130R sized .285" measured .3055" (Remington 223 brass)
7mm TCU with jacketed bullet measured .3045 (Remington 223 brass)

7-30 Waters with Lee Soup Can sized .285" measured .3055" (Remington 30-30 brass)
7-30 Waters with jacketed bullet measured .304" (Federal 7-30 Waters brass)

I checked all my brass and I did not have to neck turn any of it.

[Bloodhound689]

Okay, I went and checked my reloads and measured the end of the case neck with the bullet in place. I got the following:
7mm TCU with Lee C285-130R sized .285" measured .3055" (Remington 223 brass)
7mm TCU with jacketed bullet measured .3045 (Remington 223 brass)



7-30 Waters with Lee Soup Can sized .285" measured .3055" (Remington 30-30 brass)
7-30 Waters with jacketed bullet measured .304" (Federal 7-30 Waters brass)

I checked all my brass and I did not have to neck turn any of it.

I appreciate you doing that. Must be the bullet. That doesn't seem like a lot but it kind of Is for a finished round. I need to measure them before seating the bullet.

[garandsrus]

I would make sure your bullets are really 7mm, especially since they are pulls. I loaded a .308 bullet in a 7-30 once. The bullet did seat in the cases but of course wouldn’t chamber. It took a few minutes to figure out that I used the wrong box of bullets. The weight was correct so that must be all I saw.

I didn’t have my issues forming 7-30 from 30-30 brass. The double shoulder is pretty cool. After you pull the trigger, it’s amazing to see the new case shape.

[Bloodhound689]

I would make sure your bullets are really 7mm, especially since they are pulls. I loaded a .308 bullet in a 7-30 once. The bullet did seat in the cases but of course wouldn’t chamber. It took a few minutes to figure out that I used the wrong box of bullets. The weight was correct so that must be all I saw.

I didn’t have my issues forming 7-30 from 30-30 brass. The double shoulder is pretty cool. After you pull the trigger, it’s amazing to see the new case shape.

I thought about that too and have measured the bullet just in front of the case about 10 times just to make sure. .284

[Three44s]

As I recall you ran your FL sizer down to 1/2 turn from your shell holder. Have you tried sized but not seated cases to see if you are right on your head space.

Contenders are very picky about that.

Another trick is to use a black marker and paint a couple of your sticky cases and try reinserting them and closing your action. Look for bright marks through the dried ink.

I have found there is a bit of a dance getting cases through the initial fire forming and then a smaller one once they are fired in your chamber.

Once you get the action to close, it may not fire until you give even just a scosh more room from case shoulder to breach face.

Also, how is your case length?

Three44s

[Bloodhound689]

As I recall you ran your FL sizer down to 1/2 turn from your shell holder. Have you tried sized but not seated cases to see if you are right on your head space.

Contenders are very picky about that.

Another trick is to use a black marker and paint a couple of your sticky cases and try reinserting them and closing your action. Look for bright marks through the dried ink.

I have found there is a bit of a dance getting cases through the initial fire forming and then a smaller one once they are fired in your chamber.

Once you get the action to close, it may not fire until you give even just a scosh more room from case shoulder to breach face.

Also, how is your case length?

Three44s

I have tried it both with the die backed out a couple turns and at 1/2 turns backed out. Round seat and lock up until I seat a bullet. I just checked a few cases and the longest one was 2.037.

I will try again sometime this weekend using the tips from above.

[daved63]

I have tried it both with the die backed out a couple turns and at 1/2 turns backed out. Round seat and lock up until I seat a bullet. I just checked a few cases and the longest one was 2.037.

I will try again sometime this weekend using the tips from above.

If you haven't already done so, I would adjust the FL sizer until it touches the shell holder and size a couple of cases. Then adjust the seater die with a piece of sized brass in the shell holder and the ram at the top of it's stroke so that you are sure you are not crimping while seating the bullet. If it still won't chamber then I agree with Three44s, blacken the cases and see where the problem is.

[garandsrus]

I don’t remember how far the sizing die is screwed in when forming the second shoulder on the cases, but I don’t think it’s all the way in. I think the OP was correctly locating the shoulder since he was able to close the pistol with the formed case.

Here’s my current thought: Is the case mouth chamfered? It is possible that a flat base bullet could be partially collapsing the shoulder while it is being seated. This would cause the case to not chamber. I have done it, especially with 7 TCU brass.

Here’s how to test it:
1) Take a case and create the false shoulder. Make sure it chambers with a little resistance.
2) Load a bullet and see if it chambers
3) Pull the bullet
4) Try to chamber the case again.

If the shoulder has collapsed, the case will not chamber after pulling the bullet. This would prove that the shoulder moved during bullet seating, which should not happen.

[Bloodhound689]

There is a chance that the shoulder was pushed back a little when I sized them the second time but I think the problem lies with the thickness of the neck. I have lots of stuff to try. First I have to find some bullets. Thanks for all the tips

Garandsrus - I will try that tomorrow

[Three44s]

I have tried it both with the die backed out a couple turns and at 1/2 turns backed out. Round seat and lock up until I seat a bullet. I just checked a few cases and the longest one was 2.037.

I will try again sometime this weekend using the tips from above.

Actually I am suspicioning that 1/2 turn from the die touching the shell holder could be too much space.

My experience with 7 mm TCU is you go slow as in a couple of cases sized until you find out what your barrel and action require.

A Contender can appear to have locked up and it’s not totally. Mine have to have just a wee little bit of free space or they just click (do not fire).

You can get around the problem by hard snapping the barrel shut sometimes, once or twice. But the easy way is to keep fine adjusting your FL die until it’s just right.

Good luck on your endeavor!

Three44s

[Bloodhound689]

Actually I am suspicioning that 1/2 turn from the die touching the shell holder could be too much space.

My experience with 7 mm TCU is you go slow as in a couple of cases sized until you find out what your barrel and action require.

A Contender can appear to have locked up and it’s not totally. Mine have to have just a wee little bit of free space or they just click (do not fire).

You can get around the problem by hard snapping the barrel shut sometimes, once or twice. But the easy way is to keep fine adjusting your FL die until it’s just right.

Good luck on your endeavor!

Three44s

The click is what I am afraid of. I've read that in a lot of places. Actually I can't say that. I am having fun in this process. I just can't wait to get to the range with the few that I do have and see how they do

[Bloodhound689]

Quick update. Took the two Contenders to the range yesterday. Was able to load the 39 rounds that I had on hand and all 39 of them fired. I am pleased with these two handguns and look forward to next weekend. Plan on loading some more and going back. I will say that I need some practice with these things.

Thank you to the gentlemen that generously sent me some bullets to try out and thanks to everyone for the information on this thread.

This is a great site with a wealth of knowledge. Wish I started posting sooner.

[Elmer Fudd]

When I have sized some 223 or 5.56 brass into 7TCU, I have found a need to inside neck ream in order to be able to chamber brass with seated bullets, especially cast sized over nominal bore size.

[Bloodhound689]

When I have sized some 223 or 5.56 brass into 7TCU, I have found a need to inside neck ream in order to be able to chamber brass with seated bullets, especially cast sized over nominal bore size.

I wonder if they make an attachment for the lyman universal case trimmer for that.

[daved63]

I wonder if they make an attachment for the lyman universal case trimmer for that.

You can get an adjustable reamer that can be chucked in your cordless drill. That's what I use. You can get a set on Amazon that goes from 1/4" to 15/32" for about $25. You can adjust it to remove as much material as you want. If you want to be extra accurate you should ream the case while it is being supported in a file trim die. I have done it with and without the case being in a die, both ways work but you're not guaranteed that the reamer will not expand the neck a tiny bit when it goes in unless you have the neck supported in a die.

[Bloodhound689]

You can get an adjustable reamer that can be chucked in your cordless drill. That's what I use. You can get a set on Amazon that goes from 1/4" to 15/32" for about $25. You can adjust it to remove as much material as you want. If you want to be extra accurate you should ream the case while it is being supported in a file trim die. I have done it with and without the case being in a die, both ways work but you're not guaranteed that the reamer will not expand the neck a tiny bit when it goes in unless you have the neck supported in a die.

I found them. Thank you. There sure is a lot more to rifle cartridges then handgun isn't there

[daved63]

I found them. Thank you. There sure is a lot more to rifle cartridges then handgun isn't there

There certainly is. I guess you got a tighter chamber in your gun than the one I have. I have never had to ream the 7mm TCU. I have been forming 6.5 Remington Magnum from 7mm Remington Magnum for years and it is quite an operation. That is where I first found the adjustable reamer. If you go slow and adjust the reamer to just remove .0005" to .001" at a time they work fine. If you try to take too much material in one pass they will get hot and clog. Remember that if you change the neck wall thickness by .001" you will reduce the diameter of the neck with the bullet seated by .002".

[Bloodhound689]

There certainly is. I guess you got a tighter chamber in your gun than the one I have. I have never had to ream the 7mm TCU. I have been forming 6.5 Remington Magnum from 7mm Remington Magnum for years and it is quite an operation. That is where I first found the adjustable reamer. If you go slow and adjust the reamer to just remove .0005" to .001" at a time they work fine. If you try to take too much material in one pass they will get hot and clog. Remember that if you change the neck wall thickness by .001" you will reduce the diameter of the neck with the bullet seated by .002".

I have lots of things now to try if I run into this problem again. The 7mm TCU wasn't as bad as the 7-30. I'm going to start off with die adjustment and just work my way down the list on this thread.