243-204 wildcat?

[cabelas90]

i had a crazy idea about a 243 204 wildcat has anyone every made one my thoughts was to shoot the 55 grn bergers out of a 30 in 1 in 9 or 1 in 8 twist barrel off a rem 700 action any info or thought would be great!

 

[Trickymissfit]

way overbore! Better yet would be the 6.8 SPC case necked down and shortened slightly.
glt

 

[cabelas90]

hmm to fast or? i havnt really thought much about it other than i would want the speed of the 32 grn with the nockdown and bc of a heaver bullet!

 

[Trickymissfit]

hmm to fast or? i havnt really thought much about it other than i would want the speed of the 32 grn with the nockdown and bc of a heaver bullet!

overbore cartridges are known for their short barrel life, and lower accuracey with inefficentcey following close by. I doubt you'd gain 150fps with that big case while having a 500 round barrel life at best. The same has been well known for a lot of the wildcats off that same case unless your using big heavy bullets. The .222 mag case is about it for capacity in 20 caliber, but a shorter, but fatter case might be the ticket. How about something like a Dasher case necked down to 20 caliber?
gary

 

[cabelas90]

ive never heard of a dasher? but what i want to acomplish is something rare with that in mind i still want to be practical my thoughts have been leaning to look for around 4000fps with a 55 grn bullet in 20 cal ive hear that the 204 ruger has around a 5000 round barrel life pushing 4000fps and looking at case capicty its not jus a ton more with the 243 if you sit down and reallly compare case size atleast why ive leand that way would be because of componits being so availble like brass and such i really am glad for any input i dont reload for much but i like to tinker! what about 243wsm? the 6.8spc isnt much more than a 223 necked up wich is close to a 222 case so i wouldnt gain anything there?

 

[Trickymissfit]

ive never heard of a dasher? but what i want to acomplish is something rare with that in mind i still want to be practical my thoughts have been leaning to look for around 4000fps with a 55 grn bullet in 20 cal ive hear that the 204 ruger has around a 5000 round barrel life pushing 4000fps and looking at case capicty its not jus a ton more with the 243 if you sit down and reallly compare case size atleast why ive leand that way would be because of componits being so availble like brass and such i really am glad for any input i dont reload for much but i like to tinker! what about 243wsm? the 6.8spc isnt much more than a 223 necked up wich is close to a 222 case so i wouldnt gain anything there?

I think 5000 rounds thru a .204 barrel is pushing it. The vortex of the flame pathe is very close to the end of the neck, and I'd say 2500 rounds at best and yet still shoot tight groups.

The Dasher case is nothing but an improved 6BR case, and will hold three or four grains more powder than the .204 Ruger case. The SPC case is shorter, but much bigger in diameter. Another one to think about is the old 35 Remington case shortened to about 1.75" in length. It's a .450" diameter case, and should give you a lot more capacity (if you can use that much). The 6.8 case is pretty much a shortened and rimless .225 Winchester. There is also a 20PPC, but how it shoots I don't know. How about the .220 Swift case shotened to about 1.95" with a .25" neck and 35 degree shoulder angle? That ought to flat smoke a .204 Ruger on paper. Cases are easy to come by, and the bolt head is not a serious issue. Even a slightly shortened 22-250 improved, necked down to 20 caiber is gotta be one to think about ( 1.375" shoulder/ 1.812" oal/ with a .250" neck). I think it'd at least push the 55 grain bullets to 3750fps, and be far easier on the barrel.
gary

 

[cabelas90]

I think 5000 rounds thru a .204 barrel is pushing it. The vortex of the flame pathe is very close to the end of the neck, and I'd say 2500 rounds at best and yet still shoot tight groups.

The Dasher case is nothing but an improved 6BR case, and will hold three or four grains more powder than the .204 Ruger case. The SPC case is shorter, but much bigger in diameter. Another one to think about is the old 35 Remington case shortened to about 1.75" in length. It's a .450" diameter case, and should give you a lot more capacity (if you can use that much). The 6.8 case is pretty much a shortened and rimless .225 Winchester. There is also a 20PPC, but how it shoots I don't know. How about the .220 Swift case shotened to about 1.95" with a .25" neck and 35 degree shoulder angle? That ought to flat smoke a .204 Ruger on paper. Cases are easy to come by, and the bolt head is not a serious issue. Even a slightly shortened 22-250 improved, necked down to 20 caiber is gotta be one to think about ( 1.375" shoulder/ 1.812" oal/ with a .250" neck). I think it'd at least push the 55 grain bullets to 3750fps, and be far easier on the barrel.
gary

hmmm those are some very interesting thoughts! if a guy had the money itd be fun to play with em all and see! the 22 250 will push a 55 grn bullet to about 3600 do you think you could expect to gain anything by necking down to 20 cal? i think the bc is alittle better with the 20 cal.

 

[Trickymissfit]

hmmm those are some very interesting thoughts! if a guy had the money itd be fun to play with em all and see! the 22 250 will push a 55 grn bullet to about 3600 do you think you could expect to gain anything by necking down to 20 cal? i think the bc is alittle better with the 20 cal.

with a standard 22-250 case necked down, I doubt it. But I still think 3550fps is doable. Have not seen in ballistic specs for a 55 grain 20 caliber bullet out of the Ruger case, but you can get 3700fps out of the 45 grain bullet(max). The problem with necking down cases is that you also loose surface area at the base of the bullet. (in this case not a lot) So it's easier to push a bullet with a little more square inches of surface area at the base. Add to this the fact that you can only burn so much powder before the bullet exits the barrel; no matter what it's length. It kind of appears that 30 grains may be just about max for this bullet. I suppose that if you had a good shot out barrel and a reamer it'd be a good experiment.
gary

 

[cabelas90]

with a standard 22-250 case necked down, I doubt it. But I still think 3550fps is doable. Have not seen in ballistic specs for a 55 grain 20 caliber bullet out of the Ruger case, but you can get 3700fps out of the 45 grain bullet(max). The problem with necking down cases is that you also loose surface area at the base of the bullet. (in this case not a lot) So it's easier to push a bullet with a little more square inches of surface area at the base. Add to this the fact that you can only burn so much powder before the bullet exits the barrel; no matter what it's length. It kind of appears that 30 grains may be just about max for this bullet. I suppose that if you had a good shot out barrel and a reamer it'd be a good experiment.
gary

wow i never thought of the surface area being a factor. but that does make sense! maybe when i shoot out my 204 ruger i might try something but it just seems kinda farfetched. thanks so much for your input!

 

[Trickymissfit]

wow i never thought of the surface area being a factor. but that does make sense! maybe when i shoot out my 204 ruger i might try something but it just seems kinda farfetched. thanks so much for your input!

pushing a bullet down the barrel is nothing but pneumatics. You have a given pressure that will decrease as the volume of the cylinder increases. Of course the powder charge is still buring to create more gas pressure as the bullet is moving to make up for the loss. The pressure contacts the base of the bullet creating the piston in a pneumatic cylinder. With more square inches of area, you end up with more pounds per square inch of area at the base of the bullet. (becomes a piston on ignition) That's why it's easier assuming they are of similar weights and shape. A very good example of this is to compair a generic 30-06 with a .338-06
gary

 

[rifle 57]

A 20-250 has allready been done. Greg at GRE -TAN RIFLES has a reamer.
I cant remember how fast it is but it works fine, I have seen it shoot.