Favorite 6.5 Cartridge

[CliffM]

I have have loaded my 6.5 Sherman with 155gr vld's to touch the lands at 3.454". That is fine at the range single loading. For hunting I pushed them back to 3.385" to magazine feed and had very little if any loss in accuracy.
The 140's will be 3.4- 3.42" touching, but shoot well at 3.385" also.
Bullets from 130gr to 155gr all seem to seat very close to the top of the boattail at the base of the neck. Rich really did a good job of designing the reamer dimensions.
Cliff

 

[elkaholic]

CR and Barnesuser, I think the case OAL is the same as the 270 Win which is the parent case, so your cartridge OAL is that plus whatever bullet you use and how deep you seat it.

Right Rich?

The chamber length is actually .015" shorter than the .270 and it is throated so the 140 vld's fit just to the base of the neck at the body/boat tail junction so you get full case capacity out of the cartridge. Good for accuracy and horsepower.

 

[elkaholic]

Yes...COAL...that is my question as the nice long neck on the 6.5-06AI looks able to keep VLD bullet bases out of the powder column...which is what counts NOT just total water / powder volume capacity.
Also, Rich you mention that 6.5x65 RWS brass allows longer necks ...approx how much longer and what total neck length?
Are these rounds (6.5 Sherman & 6.5-06AI)magazine box length restricted with 140 gr Bergers/142Sierras/140AMaxs?
Sounds like you are planning of longer barrel/throat life with this design...ball park #s?

The neck length isn't really that long on the RWS but it has a really long body and is longer overall than any of the american rounds. (2.56" vs 2.54" for the .270) Also, there is no problem fitting the long 140 vlds in the magazine, loaded to the lands, in my stock 700 Remington. As I think I stated earlier, I have approx. 1500 rounds thru my Sherman and it still shoots well under .5" moa......Rich

 

[elkaholic]

My point is I don't want a single shot because the rounds won't feed thru my magazine and I don't want a nice big case that I can't fill because if the reamer throats it out far enough then the short neck contributes to poor runout and throat erosion from the hot gas pattern.
Since the 270 case shoulder is changed and fire forming changes the body taper then that changes the 270's i.e. parent case OAL.

Correct....the brass shrinks approx. .015" when fire formed. That is why I designed the chamber length at 2.525".......Rich

 

[barnesuser28]

Rich, i would like to build one of your 30/375 S.I.s one we shoot the barrel out on my dads 300 RUM, if we ever do (he hates shooting that 7.5 lb unbraked monster )

 

[elkaholic]

Rich, i would like to build one of your 30/375 S.I.s one we shoot the barrel out on my dads 300 RUM, if we ever do (he hates shooting that 7.5 lb unbraked monster )

If you shoot very much, I guarantee you will shoot the barrel out! I love my S.I. so far. Up to 3100' with 215's and one hole accuracy. Here are acouple of pics which compare the 6.5 Sherman to the 30/375 S.I. It is pretty much a Sherman on steroids (same basic design with different parents) 20 grains more capacity....Rich

 

[barnesuser28]

If you shoot very much, I guarantee you will shoot the barrel out! I love my S.I. so far. Up to 3100' with 215's and one hole accuracy. Here are acouple of pics which compare the 6.5 Sherman to the 30/375 S.I. It is pretty much a Sherman on steroids (same basic design with different parents) 20 grains more capacity....Rich

What coal with pictured round? 3.7?? We probably only have 150 rounds out of it and we've had it for 4-5 years, we need to put a break on it, its not fun to shoot at all, two full tilt 180 grain loads and i am done, yet i can shoot 15+ full tilt 280 grain loads from a 338 Lapua so i dont think im that sensitive to recoil. How is performance compared to a 300 RUM? same bolt face?

 

[elkaholic]

What coal with pictured round? 3.7?? We probably only have 150 rounds out of it and we've had it for 4-5 years, we need to put a break on it, its not fun to shoot at all, two full tilt 180 grain loads and i am done, yet i can shoot 15+ full tilt 280 grain loads from a 338 Lapua so i dont think im that sensitive to recoil. How is performance compared to a 300 RUM? same bolt face?

Ya, with my bullets seated into the lands, it is 3.727". The 215 Bergers are about 3.705" to lands......Rich

 

[MontanaRifleman]

Barnesuser, I would recommend a brake but in the mean time, I have a a decelerator slip on recoil pad that I use with my un-braked Sendero 300 RUM. I have shot as many as 50 rounds on the bench in a couple of hours and could have easily shot more.

I use it on all my un-braked heavy kickers from 7 RM on up.

 

[bigngreen]

Rich, i would like to build one of your 30/375 S.I.s one we shoot the barrel out on my dads 300 RUM, if we ever do (he hates shooting that 7.5 lb unbraked monster )

My dad has a 300WBY that has the same issue and I want to turn it into a 30/375SI so I'm putting a brake on is so he'll wear it out faster Some times a sons gotta do what he's gotta do gun)

 

[MontanaRifleman]

Rich, what action are you shooting your SI out of?

 

[elkaholic]

My dad has a 300WBY that has the same issue and I want to turn it into a 30/375SI so I'm putting a brake on is so he'll wear it out faster Some times a sons gotta do what he's gotta do gun)

Yes they do!!

 

[elkaholic]

Rich, what action are you shooting your SI out of?

BAT HR. I also have one on a B-78 ......Rich

 

[Aldon]

I have both the straight -06 and the improved. And the Sherman or similar would be very nice.

But someone replied to an old thread that they had a 6.55x55 AI and had done real pressure tests and had posted very impressive velocity.

My long term bolt plans would be to do the 30/375 SI and try the 6.5X55AI in the future.