6.5 or 7XC

Troy G · Post by **Troy G** » Tue Dec 06, 2005 10:32 am

Anybody messed around with Tubb's XC case in 6.5 or 7mm for HP silhouette?

nomad · Post by **nomad** » Tue Dec 06, 2005 1:01 pm

Wouldn't that -- with minor-to-the-point-of-meaningless differences -- be the same as the 7mm International/7mm IHMSA...which have been around for years?

Guest · Post by **Guest** » Tue Dec 06, 2005 6:33 pm

I haven't been around for years and cannot find any significant information on the IHMSA rounds with heavy for weight bullets and the powders we have available to load with today. Information I have found in loading manuals is handgun specific.

Mr. Nomad, Do I detect some sarcasm in your response:?:

My question was more to ascertain acheivable velocities with bullets like the Sierra 175 and 180gr VLD bullets in 7mm and some of the 140 gr class bullets in 6.5. I also wanted to find out what the 6XC brass availibilty and quality was like.

Troy G · Post by **Troy G** » Tue Dec 06, 2005 6:39 pm

It would appear that I got my shorts in a bunch with my last post on this thread. I also was not logged in so it posted as guest and I do not have the option to edit my post.

I apologize Mr. Nomad for my response to your statement as I did not read the other responses to my other post on the all around HP cartridge.

nomad · Post by **nomad** » Tue Dec 06, 2005 7:41 pm

Not a problem...I wasn't being sarcastic but I probably could have been less abrupt. (When I want to be sarcastic, it's usually easy to notice! I'm trying not to do that any more though...) lol

Yes, the information is mostly handgun specific but I think we can extrapolate it pretty easily. I also think that Theodore is on the right track with the heavy-bullet 7mm idea -- and these short-but-bigger-than-a-BR 7s look (in theory) to be the best answer yet to the problem. I'm not sure how much we're chasing our own tails in the pursuit of 'recoilless' rounds but like Tubb says, even if you can live with it, recoil can't help.

AFAIK, Tubb has got the problems resolved with 6XC brass now that the 3rd(?) generation brass is out -- but I've always been a strong proponent of Lapua components and when/if their 6.5 case actually becomes available, we'll be unlikely to have questions about brass consistency to worry over.

I expect that this rule change is going to be beneficial. We'll have to wait and see if scores reflect that...

dwl · Post by **dwl** » Thu Feb 09, 2006 7:06 am

Last I 'member, we was waitin' for the next episode of Dan's World in which he was involved with a 7mm beauty. Did I miss that or is it on the other channel?

Troy G · Post by **Troy G** » Thu Feb 09, 2006 7:30 am

I went ahead and did a 7mm TKS. This little case did not impress me in the 6.5 config. but in 7mm it is the cat's meow.

I did not try many different powders yet as the project was finished in the middle of winter up here in Sask, Canada. Anyway, loads with 180gr Bergers were running into the 2650fps range using VV-550. VV-150 was not working for me as my barrel seems to like powder a little faster. With Varget I was getting 2600 fps but accuracy was not there so I backed down to 2550fps and this is what I have been shooting during the winter.

Once it warms up here I will retest my loads and see what is shaking as I suspect I may have to back down a bit. I also want to try some RL-15 and have some Ramshot Big Game that will meter like water. I could be happy just shooting plain old Varget.

Ram performance is awesome! The 180gr bullets at 2550fps literally knock the rams back and off the rail. With my 6.5 TKS shooting the 139gr Lapuas at 2675fps the rams would SLOWLY lean backward and fall over, it looked like everything was in slow motion. With the 7mm the rams go spinning off the rail or are pushed off backwards and then fall. I even tested the 7mm on my home range rams that were made from salvaged 3/4" plate that weigh almost twice as much as what rams should weigh and the results are pretty impressive.

My set-up is 26" Hart barrel with Shilen reverse taper, a nd1/8" twist. Dave Kiff worked his magic on the reamer and my local smith, Craige Douglas did an excellent job of all the metal work. The stock is Mark's standard stock from Ian.

If my results are any indication of normal than I would say that a bigger case is not necessaary. I won't lie and say that I am not running high pressure loads but I just necked up my 6.5TKS brass that has been fired close to 15 times and then started shooting as a 7mm. I do not have a FL die in 7mm TKS and the brass I have been using as 7mm has now been fired four times and has not needed to be sized or bumped except to run through a neck bushing die ot get proper neck tension.. I got Dave to spec the reamer with very tight dimensions based on brass that I sent in.

My two bits.

Troy

Guest · Post by **Guest** » Fri Feb 10, 2006 9:45 am

I'm a might confused here. "For every action there is an oposite and equal reaction". A 180gr bullet launched at 2600fps won't "feel" significantly different from the same bullet at the same speed launched from a 7-08 or a .284 or a .280 for that matter. Where is the logic or reason that has one using a thimble sized case for "reduced recoil" and then try to get 7-08 velocities out of it?
"High Pressure"? no s**t!! You're about a nano moment from three rings of steel embeded in your forehead!! For God sake listen to reason, if not for yourself then for the innocent shooters to your left and to your right who don't know there's an accident looking for a location. 2350-2400fps is more than enough with a 162 bullet to reliably take rams (want more? 7-08), 180? major enough, and you're still in "high pressure", "danger" on a hot day.
We've messed around quite a bit with the shortened up, blown out, necked up little BR cases and they are phenominal in blast containment, until you find the "sweet" spot. You're there!! These little cases may not show "pressure" in the sense of case head shiny marks or blown primers first (especially if it's a "tight" chamber). At the 60,000psi and up range where you wish to play, things happen real fast. The cool northern temps have drawn you far off the side of the safety net my friend. After tinkering with the little gun ideas and all it's finickyness, I went back to the 7-08; that's probably why the .260 or 7-08 are still used by most of the top shooters
HP is a game I thoroughly enjoy. With shooter numbers shrinking and ranges getting fewer and farther apart, catastrophic failures of firearms at matchs are not in the best interest of the sport. It is not my intent to embarrass or "get in the face" of anyone, the number of my posts will speak of the fact that I'm not a prolific poster, this one struck a nerve. I initially had thought to send a PM but then noticed that 177 other people had already checked out the post. Let's be careful of how we present data on these forums. I'd love to see all of us shooting in Master class, but that'd be tough without fingers or eyes. I was hoping someone else would respond so I wouldn't, but hey, there's one in every crowd, guess that'd be me.
Carroll

Troy G · Post by **Troy G** » Fri Feb 10, 2006 11:17 am

Carroll,

I would like to reply to your post as rationally as possible without resorting to personal attack. Although I must say your post has really pissed me off!

At least you left your name so that I knew who was attacking me. You should have used your better judgement and emailed me or or pmed me before you made the statements you did.

I always laugh at how easy it is for one complete stranger to imply that another complete stranger is an unsafe idiot who has no regard for personal or public safety and has no idea how to reload, on a public forum no less.

You seem to think this is the first wildcat cartridge I have ever played with. Did I say in any of my posts that these results were going to be typical if you run out and do what I did? Always amazes me when one person does something and gets better than average results someone always has to call bullshit and then there is the usual you are going to blow your self up doing it. If you go back and read my post you will see that I said that I am aware of the fact that the loads I was talking about will have to be re-evaluated for pressure in the summer. Where did I list my loads that could be duplicated? Oh yeah, I did not list my loads only stated velocity that I was getting from my set-up. Surely you are aware of the fact that different reamer specs, barrels, and cases can produce varying results?

The goals for my 7TKS project were to exceed the ram performance of my 6.5 TKS and equal the wind deflection of my .260 at the ram line. I never said that you have to shoot bullets at 2550fps to take rams. Since rams only account for 25% of your score I don't know why your busting my chops over this. Load as slow or as fast as you want. After trying a couple of different things with my 6.5 TKS including a couple of barrels and talking with several silhouette shooters I thought I could use a 7 TKS and get what I wanted.

Carroll and others, shoot whatever case you like but I have never had consistency and accuracy shooting a case 1/2 or 2/3 thirds full of powder and trying to load in a low pressure node. Why use a 7-08 when a smaller case will do what a bigger case needs to do? But you obviously do not buy into this. Why do you think I started the thread I did? I, like everyone else, is looking for a better mouse trap.

You may want to contact Dan Theodore and tell him that he is nano seconds away from killing himself and others as he tested a regular 7mm BR with 175gr bullets at 2500 fps. The 7BR will likely have about three grains less water capacity than my 7 TKS. His thread over on greybeard was much more popular than this one. Think of all the innocents you could have saved if you would have only posted there as well.

I appreciate your concern but am annoyed at how you handled this!

Guest · Post by **Guest** » Fri Feb 17, 2006 10:59 am

Troy;

Thanks for sharing the info. While I recognize the concerns of over pressure (ala last years accident at Phoenix) I'm still very interested in what you and Dan have been doing. I shoot smallbore now but I figure I'll dip my toe into highpower in a few years. Better to get educated first.

How does the volume of the 7mm TKS compare to the 7mm-08?

dwl

Troy G · Post by **Troy G** » Fri Feb 17, 2006 11:29 am

I personally would not go down the TKS route if you are just starting out in Highpower. There is no need to fool with the special dies and fireforming of cases. Wait a bit and go with Lapua's new case or shoot David Tubb's 6XC once Norma rolls out with the brass. Either case will give you the velocity you need to take rams without having to worry about pressure, although it sounds like the 6.5x47 will be built tough.

IN MY OPINION a round like the 7-08 is not needed as smaller cases will do drive the bullets fast enough to take all the animals.

I am not saying that the 6.5 TKS or the 7 TKS is the wonder cartridge. I started playing with the case and had custom dies built and wanted just a little more ram performance. I thought I may be able to do what I needed to do with a 7mm and it worked for me.

I have been looking at different cases for a couple years. I wanted to try a XC design and was looking into importing some 6x47 Ruag brass. Now that Lapua and Norma are getting on board with the cases I mentioned above I would not fuss with a 7 TKS. If I did it over again I would build one rifle in either case design and shoot it in both classes.

dwl · Post by **dwl** » Mon Feb 20, 2006 11:36 am

Troy;

Thanks for the reply. I will be holding off for a year or two still. So much to learn with the smallbore. From what I've read the 7mm seems to be a bit more reliable on ram knock down than the 6.5s but people are still testing. I'll read with interest anyones measured results.

A note about Carroll's recoil remarks, recoil is not just the mass of the bullet at whichever velocity, it is the mass of ALL the ejecta, i.e. the bullet and the powder (and wads if you shoot shotgun or black powder).

Larger capacity cases are not as efficient at converting chemical energy into kinetic energy as smaller cases. Therefore a smaller case can be used to shoot a given bullet at the desired velocity with less recoil than a larger case can.

dwl

ajj · Post by **ajj** » Tue Feb 21, 2006 7:17 am

As a rough rule of thumb, a change in the weight of the powder charge changes the recoil half as much as the same weight change in the bullet.
I shoot a 7BR so I like the idea of the small, efficient cartridge. But the ram load enlarges primer pockets after two shots. I wouldn't continue to use the load if I didn't have a benchrest action. I understand I just admitted that I'm maybe not all that bright. CB is one of the most friendly and helpful guys in the sport. Please don't let his enthusiastic writing style put you off. People really have been hurt pushing the small cases which is often what we end up doing to take rams.
I think the case between the BR and the "08" will probably prove best. But for almost everybody, including me, it's hard to beat the 260/7-08. You can always load them down for the C-P-T and then lay the heavy bullets on the ram without stressing the brass.

Troy G · Post by **Troy G** » Tue Feb 21, 2006 12:33 pm

AJJ,

As a matter of interest would you mind telling me what velocity you were running with what bullet that only allowed two firings before the primer pockets were enlarged in your 7BR? What brass were you using. You can email me at [email protected]

ajj · Post by **ajj** » Tue Feb 21, 2006 1:18 pm

PM sent. Any advice appreciated.

6.5 or 7XC

6.5 or 7XC

My apologies

7mm

My Opinion . . . Here it goes.

7mm TKS

Cartridge