Making 243 brass

[NSDQ]

I am a fan of lake city brass in addition to Peterson.
I recently bought my wife a 243 and sized 75 308 cases down (LC brass). Trimmed to length and turned the necks to the shoulder to .0140.
When seating 95 gr SMK the seating pressure/ neck tension is FAR greater in these than new FL sized cases.
Not sure why
Also annealed the cases

 

[STOMP442]

Need to turn your necks. When necking down cases like that the necks get thicker and will also cause donuts. Turning .002" or so off the necks should fix your problem.

 

[243winxb]

308 to 243-

Donut? Missed when brass was outside neck turned?

Just buy new 243 win brass.

 

[mikecr]

Donuts are not caused by down sizing.
Did the annealing increase seating friction?

 

[nmkid]

If I remember correctly I have some .243 cases stashed somewhere. PM your address and I will send them to you if I find them.

 

[wkdickinson]

I am a fan of lake city brass in addition to Peterson.
I recently bought my wife a 243 and sized 75 308 cases down (LC brass). Trimmed to length and turned the necks to the shoulder to .0140.
When seating 95 gr SMK the seating pressure/ neck tension is FAR greater in these than new FL sized cases.
Not sure why
Also annealed the cases

If you like Peterson brass (as I do), why would you make 243 cases from LC308 brass? We are involved in a sport that is not for the economically timid LOL I find it hard to believe th LC brass is better than Lapau or Peterson.

 

[searcher]

Yeah. You definitely need to turn the necks down on your brass. Back in the "Hillary crisis" I had to make some out of Federal .308 which nobody at the range wanted. I can tell you I had to take WAY more than .002" off. I'd measure the neck on a loaded factory .243 case , then measure one of your loaded cases that you made. The difference is what you will want to turn off unless you have a bushing die AND the unturned measurement is within .243" factory specs. You would know if it is tight when closing the bolt. You should feel no extra resistance closing it on your loaded cartridge.

 

[NSDQ]

LOL
forums are great.
Those that stated I should turn the necks must have missed in my post that I do turn them.
Also please do not post a reply asking why I use a certain brass. Either contribute by offering solutions or stay quiet.
Thanks to those that offered a solution.
I hope I didnt over anneal. I would think that the case would crush if it was too soft...?

 

[olddav]

You didn’t mention the process used to size the brass. My first thought is install a larger bushing if that’s the type die you are using. The second is check the necks to see if they are uniform from top to shoulder. Again I don’t know your setup so I’m just guessing.

 

[Nick Caprinolo]

LOL
forums are great.
Those that stated I should turn the necks must have missed in my post that I do turn them.
Also please do not post a reply asking why I use a certain brass. Either contribute by offering solutions or stay quiet.
Thanks to those that offered a solution.
I hope I didnt over anneal. I would think that the case would crush if it was too soft...?

Your attitude leaves much to be desired. If i were a new poster as you are, I would soften my responses to folks are who simply trying to share their experiences with you. They are not criticizing you, they are trying to be helpful. The fact that you hope you did not over anneal, tells me that your experience is limited. If you knew what you were doing, you would know if the brass was prepared properly.

First, .014 neck thickness may be a little too thick but not by much. You don't mention in what order you processed your brass. You should anneal first and then do the rest of your brass preparations. Second, after firing, brass retains burned powder residue and depending on how you clean it, it may cause the increased pressure you are experiencing. Are you using lube in the necks? Further, unless you resize new brass, it may be a bit different than the brass you resized yourself. Take your LC brass to the range and fireform it, Bring it home and resize it. Measure it and do what the gauges tell you.

You have spent hours upon hours on this project, and have not achieved a satisfactory outcome. $90.00 would have bought you the best brass possible and given you at least 30 firings per round, if properly cared for.

 

[Uncle Ed]

I am a fan of lake city brass in addition to Peterson.
I recently bought my wife a 243 and sized 75 308 cases down (LC brass). Trimmed to length and turned the necks to the shoulder to .0140.
When seating 95 gr SMK the seating pressure/ neck tension is FAR greater in these than new FL sized cases.
Not sure why
Also annealed the cases

I have a Savage Stevens 200 .243 and a Savage .308 and I ordered some bulk once fired Lake City 7.62 brass. I then ordered a 7mm-08 case forming and trim die for the first case forming and then size the case in a .243 full length die.

Things that I noticed.
1. Reducing the neck diameter increased the case neck thickness variations greatly.
2. Neck turning with these thicker necks would cause the turning mandrel to score the inside of the necks using three types of lube. This left the inside of the case necks rough and would increase seating force.
3. Neck turning these thicker necks will increase the size and how soon the brass flow creates donuts.
4. Buying Winchester .243 brass was far less work and these cases were thinner and had more case capacity.
5. Trying to be a cheap bastard and thinking you have a better idea isn't always the answer.
6. I'm still a cheap bastard because I didn't buy any .243 Peterson brass and kept my cheap ass image.

I still buy bulk once fired Lake City 5.56 and 7.62 brass for my AR15s, and bolt actions. But I also know you can't make a silk purse from a sows ear. Lake City brass is better than average Remington or Winchester brass in quality and uniformity. "BUT" it is not in the same class as Lapua or Peterson brass.

243 Win Cartridge Guide
https://www.accurateshooter.com/cartridge-guides/243win/

.243 Win For Tactical Comps
We asked GA Precision’s George Gardner why he chose .243 Winchester for his Tactical Comp Gun. He replied, “Why would I run anything else? Think about it. I’m sending a .585 BC 115 at 3150 fps–that’ll shoot inside the 6XC and .260 Rem with ease. I’m pretty sure I have found the Holy Grail of Comp Rifles. There are no brass issues like you can get forming .260 brass. I don’t have to worry about doughnuts, reaming necks–none of that. And the choice in brass is great too–run Lapua if you want max reloads and great accuracy. Run Winchester if you’re on a budget, and so you won’t cry if you lose some cases in a match.

 

[Bill K]

. Trimmed to length and turned the necks to the shoulder to .0140.
When seating 95 gr SMK the seating pressure/ neck tension is FAR greater in these than new FL sized cases.
Not sure why
Also annealed the cases[/QUOTE]

Have you measured your brass neck thickness ? Even though you trim and all. Try to get your neck thickness around .013 and that might end your tightness issue.

 

[Tommie]

Also please do not post a reply asking why I use a certain brass. Either contribute by offering solutions or stay quiet.

Came in here sporting quite a ‘tude. Best of luck.

 

[jackson1]

Have an old set of RCBS dies for making 243 out of 30-06 brass. Tried it a few times, back in the day military 30-06 was quite common (I'm referring to the 1970's). If memory serves that old military brass was quite a bit heavier than purpose built 243 Winchester brass. I was young and attempted to make every thing from 22-250 to 35 Brown Whelen. Sorry I don't get reasoning for your project.