Requirements;

Any action

Absolute minimum recoil( based on cartridge only).

Maximum hunting range 225 yds.

minimum energy 1100 ft.lbs.at 225 yds.

minimum trim of parent case.( length and neck turning )

Parent case readily available in large quantity.

Easily full length sized.

Fire forming ALMOST non existant.
Case dimentions, caliber and bullet weight:

parent case;***********.308

Max case length;***********2.030"

caliber;***************6.5mm

Neck length;**********.350"

Max. neck out side dia;***.395"

Shoulder angle;**********30 degrees

Dia. at shoulder body junction;************.457"

Minimum bullet weight;**************129grains

OAL=[COLOR:RED]*****2.915[/color]
This is kinda what I had in mind for filling out the info. I think Jeffeosso is close with the 250-3K if it had the long throatand used in a bolt action rifle to match but it ain't no new wildcat. Let's face it, if you are looking for a nitch to be filled in performance you're singing from the wrong hymnal. Of course if you want to make one shot kills on blue whales you may have an opening. See if you can fill in the chart and maybe some kind soul can draw them up and post them. Any kind souls out there? roger
I have a .358X41 similar to the "35 BR" Recoil with it far excedes the 250-3K and never could be totally effective at 225 yds. with 1100 ft.lbs.Never happen.

I say 30-30 or 35 Rem performance meets this goal.

Both can be had on a BR case size.

A 35 BR would be the bees knees on mule deer but a horrible target cart as the case was designed for.

I would say the 35 Rem bullets like the 180 Hornady Spire Point in a necked up BR case able to fit the micro actions and get easily 35 Rem performance meets all of these requirements.
use BR brass or form from any .470 based cases like the 308 or 30-06 cases. 1.525 case length. ,385" neck diameter, 2.25" max oal and all other dimensions the same as the 6 BR case. Minimal recoil and max damage out to 225 yards. Perfect mule deer wildcat.
Cheap brass and bullets to boot
rebore an existing Savage 6 BR gun that you can order today.

Or just buy a 35 rem lever gun
But hey... this is wildcating.
The 30 BR has been done but the 35 rem bullets are better for this class of game in terms of expansion and heavier bullets.

Necking up the 6 BR Norma cases in two steps or fireforming will not be hard and would not need neck turning I think.

The 30 BR wins competitions and spouts the 115 grain range of bullets at 3,000 fps and has been used on varmints to deer.

If shooting 180's @ 2,400 this will be purrrr fect or pistol bullets @ 3,000 fps for devastation on small stuff.

http://www.6mmbr.com/30BR.html

If that is too much recoil then a 30 or 35 PPC will do the trick. Some have already done the 30 PPC but as a target gun but using 30-30 hunting bullets will be a good Mule Deer zapper.

The 35 Gremlin with the link in my tagline will be near exact what a 35 PPC is and is already shooting and getting 35 Rem performance.

a 30-223 cut back to 1.6" would be low recoil but lacking on smack down.

Good intention, but this is a wildcat that SERIOUSLY would over lap just about every cartridge in existence from .243 to the 30-06

I'm trying to think of SOMETHING....but man, I'm coming up with a blank!

How about a .395-06?

A medium bore micro action deerslayer does not have much overlap

boom stick, did I read your post correctly? Did you say 30BR with 155 gr. bullets at 3000FPS?

any action and minimum recoil AND light bullets? ? 250 savage . drive through please ,, that answer is 100+ years old

several others ..22HP, 7x57, 8x57, 30-40, 30-30, 32WCF ,,,

and, the answer to the wildcat..
257 jls -- 300wsm to 25, no other changes .. i had the reamer on order for months, until the DAY winchester released the prints, then it was cut..

yes, it was nearly a 257 weatherby ... and BORING .. bang, flash, fast bullet, ittybitty groups ..

how about a 7mm (120-140gr bullets)on the 250 Savage case? If we are only going to 250 yards, that should produce the needed numbers. Or maybe a 6.5x376 Steyr?

Wouldnt the 6.5x47 be the ticket there?
I wondered if instead of shortening,trimming/reaming 308 base cases, if 22-250 brass would be long enough blown out?
All the 250 sav brass I've measured had very undersized bases, .463 or so and not all that tough a case in general it seems.

quote:

Originally posted by DocEd:
boom stick, did I read your post correctly? Did you say 30BR with 155 gr. bullets at 3000FPS?

Typo. Thanks I corrected it. should have read 115 not 155.

What you have designed there is a long neck 6.5 Creedmoor.

Good thing is you could use Creedmoor brass and rounds in a long neck version chamber.

Bartsche...

The 35 Gremlin is doing good so I don't know why a 35 BR would be bad

a 180 grain bullet only needs to be traveling 1,660 fps to meet your 1,100 fpe requirement.

If a 180 Hornady Spire Point is launched at 2400 fps will this not be going 1660 fps @ 225 yards???

A 115 grain bullet launched at 3,000 fps only needs to be traveling 2100 fps to meet that requirement.

I think both the 35 and 30 BR will do that at 225 yards.

Can anyone with fancy ballistic programs confirm this?

I've taken mule deer at 50 yards, 350 yards, and everywhere in between. Most shots, however, have been on the longer side. Last time, I used my 7mmRemMag with 150gr Partitions.

What you are thinking about doing isn't much different than my 7-08AI set-up, except my shoulder measures .461" and uses the 40 degree Ackley angle. Feeding is fine, and it shoots 140gr bullets very accurately just under 3000fps. It will go faster, but I like the accuracy at just under 3000fps with only a 22" 11 twist Shilen.

Not a wildcat but the 280 British might be worth a gander

Kinda like a 7-08 but shorter

http://en.wikipedia.org/wiki/.280_British



Bullet diameter .284 in (7.2 mm)
Neck diameter .313 in (8.0 mm)
Shoulder diameter .448 in (11.4 mm)
Base diameter .470 in (11.9 mm)
Rim diameter .473 in (12.0 mm)
Rim thickness .049 in (1.2 mm)
Case length 1.71 in (43 mm)
Overall length 2.54 in (65 mm)

Start with a 7x57 case, neck it down to .25 cal., some people will want to change the shoulder angle, chamber it in a nice light easy to carry and handle rifle and...............oh wait I have one already and it kills deer like lightning.
.257 Roberts

I'm very satisfied with my 270-08.
In a Rem 700 Ti it weighs 6lb.4oz. scoped

Why .457... why not 7mm/30rem. maybe get one more down.

Well, you could reinvent the wheel. Or use that .260 rem. I advise the 6.5X55 though.

Bartshe...

It seems I am correct about the energy and range requirements and not only that this is from the smaller case and a 17" barrel on an ar15!

Here are the results of the 358 Gremlin a necked up 6.5 Grendel case

A 35 BR would get you even more oomph!

I did some research and have found out the 35 BR HAS been done.

Let's keep this thread going for a loooong time. I'll make a reamer--at 10% off regular price--for anyone participating in this discussion, and who describes his wildcat during the discussion. What a deal!

Dave Manson

My list includes:

25 Souper Imp (30, 35 or 40 deg)
257 Bob AI
25-6.5 Rem Mag
260 Imp
6.5x55 Imp
6.5x57 Imp
6.5 Rem Mag

Welcome Dave

quote:

Originally posted by DManson:
Let's keep this thread going for a loooong time. I'll make a reamer--at 10% off regular price--for anyone participating in this discussion, and who describes his wildcat during the discussion. What a deal!

Dave Manson

25 x 6.5 RemMag...I like it.

If the original post didn't include minimal case modification, I would be curious to tinker with a shortened .284 win case in .243-7mm. I mean it should have a bump in capacity over the 308 family, and with a shorter body but longer neck you wouldn't have seating issues like the xxx-284 wild cats can run into.OH! And I would do it on a CZ527 mini action.....maybe .223 length case. Boom stick you can usually shed light on my ideas what do you think?

quote:

Originally posted by boom stick:
Bartshe...

It seems I am correct about the energy and range requirements

It can be seen by whosever information you are quoting that you might get the idea that you are correct. The fact is that a Speer 180grain PSP 35 caliber can have a muzzle velocity of 2361 FPS. but at 225 yds the velocity will drop to 1585 fps.with an energy level of 995 ft.lbs. Does this mean your proposed cartridge is bullet manufacturor sensitive or marginal just at best?
I was hopeing this thread could be a creative happening and not just a session.
Can't help feeling you can do better and still follow the original guide lines. Hey with that reamer offering you might get a chance to really create a wildcat of your own and not just a lot of conversation. roger

I think out of a 22" micro action bolt action those requirements can be met with a Gremlin or a 35 BR

I understand that you want more oomph at lower recoil @ 225 yards so a smaller bullet is needed.

It seems what you desire is a 6.5 MS or newton short and I think that is a good niche.

For a short, light, low recoiling rifle that would get the job done, what about the 6.5 Grendel. 7.62x39 brass is everywhere, and Lapua brass in any one of many configuration to neck to 6.5 would make this an excellent choice.


Von Gruff.

quote:

Originally posted by boom stick:
I understand that you want more oomph at lower recoil @ 225 yards so a smaller bullet is needed.

It seems what you desire is a 6.5 MS or newton short and I think that is a good niche.

Forgetting all the existing cartridge designs perse, this execise was intended to see the thought process approach others would take in arriving at a wildcat design. The idea that these wildcats we design here will outperform "all" existing cartridges in this selected area or catagory is doubtful at best. This is for gaining insight into how others think
Example only! One might start with what they think is the minimum bullet weight needed to get the job done. Just for shits and giggles lets suppose that this designer favors 120 gr. bullets. They than look at what calibers offer good cup and core in this weight. They might select the cup and core because the anticipated velocity levels to meet the design criteria does not dictate premium bullets. At a quick glance it is seen that this bullet weight fits nicely from 25 caliber to say 7mm.
FACTORS YOU MIGHT WANT TO CONSIDER
SD and BC favor the smaller calibers.
The velocity at 225 yds.must be at least equal to 2100 fps with a 120gr. bullet.
Barrel length least affects the larger calibers with fixed usefull capacities being the same for all.
The smaller calibers digest the slower powders a little better but the gas exits with a higher velocity and a little more mass contributing to a scosh more recoil.
Holding the usefull capacity to about 2.5cc minimum would seem to satisfy the 2100fps. figure without trying to push pressure to the max. we know this from existing cartridges.
To meet the case availability requirement most any of the .308 clones would do.
Meeting trim minimum requierments can be met with demensional design slanted toward meeting the 2.5cc capacity.
If we did a 25 caliber it would certainly do the job but the 120gr. bullet is about as large a common bullet as we can get. A step up to the 6.5 gives you a little more versatility in bullet weight availability.
With a max.OAL of 2.800" the shorter actions can be used.
Stuff like this is what I had hoped to hear from you along with your final configurations. roger

Here's a q? I have. Is there a formula for the best bullet for a caliber. I know "best" is subjective.

I suggested 7mm/30rem which is probably too close to a 6.8 rem and may be the 7mmTCU?

Should feed easier than "short and fat"

here are some stats for the 6.8 with 115
6.8mm Rem. SPC (115 Sp)
vel=2800
vel @200=2262
me=2002
me@200= 1307

I'd go with 139-140gr. in the 7mm.

rich

It's been a while since I've posted, but in doing some research for a new rifle, I saw on Reloadbench.com that a group effort there had come up with the 264RLB, an improved 6.8 Rem SPC case necked to 6.5mm. Results are showing 120gr and 125gr Noslers to attain 2600-2800 fps, depending on barrel length.

Althought this would make a 300+ yd deer rifle, I think this would satisfy the parameters of Roger's query.

Thoughts?

Bob

The perfect cartridge has already been invented...

quote:

Originally posted by B Stephenson:
It's been a while since I've posted, but in doing some research for a new rifle, I saw on Reloadbench.com that a group effort there had come up with the 264RLB, an improved 6.8 Rem SPC case necked to 6.5mm. Results are showing 120gr and 125gr Noslers to attain 2600-2800 fps, depending on barrel length.

Althought this would make a 300+ yd deer rifle, I think this would satisfy the parameters of Roger's query.

Thoughts?

Bob

Maybe a quick twist long barrel 25-6.8 SPC might be the shit with 115 to 120 grain bullets

Any thoughts on a 257 SPC?

Should be light recoil and a 600 yard shooter!

Varmints to target to deer...


With the same 115 120 grain weight bullets as the SPC you will have similar hunting velocities of 2700 FPS but much better down range performance while still doubling the normal 223 bullet weight or shooting say the 100 grain bullets around 3,000 fps performance and target shooting.

Interesting IMHO

quote:

Originally posted by bartsche:
Requirements;

Any action

Absolute minimum recoil( based on cartridge only).

Maximum hunting range 225 yds.

minimum energy 1100 ft.lbs.at 225 yds.

minimum trim of parent case.( length and neck turning )

Parent case readily available in large quantity.

Easily full length sized.

Fire forming ALMOST non existant.
Case dimentions, caliber and bullet weight:

parent case;***********.308

Max case length;***********2.030"

caliber;***************6.5mm

Neck length;**********.350"

Max. neck out side dia;***.395"

Shoulder angle;**********30 degrees

Dia. at shoulder body junction;************.457"

Minimum bullet weight;**************129grains

OAL=[COLOR:RED]*****2.915[/color]
This is kinda what I had in mind for filling out the info. I think Jeffeosso is close with the 250-3K if it had the long throatand used in a bolt action rifle to match but it ain't no new wildcat. Let's face it, if you are looking for a nitch to be filled in performance you're singing from the wrong hymnal. Of course if you want to make one shot kills on blue whales you may have an opening. See if you can fill in the chart and maybe some kind soul can draw them up and post them. Any kind souls out there? roger
I have a .358X41 similar to the "35 BR" Recoil with it far excedes the 250-3K and never could be totally effective at 225 yds. with 1100 ft.lbs.Never happen.

Simple:

Start with a 30-06 case.
Neck down to 7.03mm
Load it with 7.03mm 130 grain bullets
Call it the 7mm Jack O'Conner

Here is what the 257 SPC would look like.
Similar velocities as the 6.8 with the same 115 to 120 bullet weight for hunting but able to go all the way down to the 75 grain bullets for varminting.

100 grain bullets @ 2800 should meet your recoil and energy requirements.

Here is a wildcat I plan to eventually chamber, the 8x43mm "Kurz".

It is a 8 Rem Mag neck and shoulders on a short 284 Win case. To form the brass I cut down a 8 Rem Mag FL die to where the 284 base of .500 matches the diameter of the die, which works out to be approximately 43mm in overall case length. The rebated rim is .473 that should work with most bolt faces in short actions. The drawback to using shorten 284 cases is having to ream the case necks.

If I did the calculations in QL right, the case capacity comes out to be 51 grains H2O. I also used QL to predict performance using a range of three bullet weights and limited max chamber pressure to 52,000 psi keep recoil down and extend brass life. Using a 24" barrel and powders like IMR 3031, H335, and W748, I get pretty optomistic numbers like 3000 fps for the Hornady 125 bullet, 2800 fps for the Hornady 150 bullet and 2500 fps for the Hornady 195 bullet.

For Mulies, the 150 and associated trajectory would be the favored bullet in this cartridge.

Nels

quote:

Originally posted by Nelsdou:
Here is a wildcat I plan to eventually chamber, the 8x43mm "Kurz".Nels

Nice approach,Nels. Like your thought process. roger

These 100 grain speer spitzer boat tails I see as an ideal bullet for the 257 SPC

Shooting the lighter 100 grain bullets faster will give you the FPE of the 6.8 but at longer ranges and nearly doubling the bullet weight of the 223.

I guess if anything that would be the "Magic" or niche for this cart. delivering the promise of more smack down of the 6.8 SPC but at longer range and higher velocity

Here is a pic showing the 8x43, one formed from Swiss brass and one from 284 brass, next to a 8x57. All are wearing the 150 Hornady. These 8x43's as shown should shrink in length and have better defined shoulders after firing in a chamber.
[IMG:left] [/IMG]
The plan is to use the 284 brass to cycle through a short action Savage with .473 bolt head.

Nels

Should be a nice 8 Mauser equivalent
What is the capacity?
8Mauser is 63 grains

quote:

Originally posted by Nelsdou:
Here is a pic showing the 8x43, one formed from Swiss brass and one from 284 brass, next to a 8x57. All are wearing the 150 Hornady. These 8x43's as shown should shrink in length and have better defined shoulders after firing in a chamber.
[IMG:left] [/IMG]
The plan is to use the 284 brass to cycle through a short action Savage with .473 bolt head.Nels

Yours is the most sensible short fat cartridge for game in the lower 48 that I have seen. The idea of holding the pressure to below 52000psi. shows intelligence,IMHO. It may not offer the lowest possible recoil but it really is well thought out. roger