goodgrouper
Well-Known Member
It has gone to the 2nd page now under "conflicts between Weatherby 30-378, -----"
Kirby, I answered your post about the 338
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Fiftydriver
Official LRH Sponsor
GG,
Please explain something to me if you will. I may have been breathing to many fumes from the lathe so bare with me /ubbthreads/images/graemlins/grin.gif!
If you take two cases, both using a 300 gr SMK 338 bullet.
Both seated to the same 3.675" oal.
IF you take the two cases and give them both the exact same shoulder configuration and shoulder diameter, But have one case that has a case body length and case length .100" longer then the other one, How exactly does the shorter case have more volume?
A perfect example of this is my 270 Allen Mag. The original design was based on the 338 RUM case with very similiar case dimensions as what you listed you want in your 338 Thunber(good design by the way /ubbthreads/images/graemlins/grin.gif!!)
Based on the 338 RUM case, the original 270 Allen Mag formed case would hold on average 118 gr of WC872 when filled to the case mouth. This was an average of 10 cases.
In testing I quickly discovered the the 270 bore diameter could easily handle more case volume with the heavy bullets and forming out of the longer 7mm RUM cases was simplistic to the extreme so I redesigned the reamer and tested the new 270 Allen Mag design based on the 7mm RUM. From the Shoulder/case body juntion, the two designs were identical to the case mouth. Shoulders were identical in angle and diameter and the case necks were also identical in length. Only difference was that the 7mm RUM based 270 Allen Mag had a 0.090" longer case body then the 338 RUM based version.
In measuring the same number of 10 cases with the new 270 AM design, the case capacity when filled with the same WC872 to the case mouth had increased to 126 gr.
So given the case shoulder and necks volumes are identical, the longer case will have 8.0 gr more capacity then the shorter case design.
Now rememeber that bullet seating location is unchanged, both are seated to an over all length of 3.675" to feed through the Rem 700 mag box. Since the longer case provides more case volume AROUND the bullet and farther up the bullet, it offers more capacity over the shorter version of the 270 Allen Mag. It also added roughly 100 fps more velocity potential as well.
This pic shows the difference between the 257 Allen Mag(left), original 270 Allen Mag based on the 338 RUM(middle) and the final design of the 270 Allen Mag based on the longer 7mm RUM case.
You can see that all three are loaded to the same 3.675" oal to feed through the Rem 700 receiver but it is clear why the 7mm RUM based 270 AM offers more capacity then the 338 RUM based version.
The 338 RUM and the 338 Edge are exactly in the same boat as the 270 AM. Only real difference is that the Edge has a longer body portion of the case.
That said, with your design, you can match the capacity of the 338 Edge in a shorter case, no arguements from me there. My 257 Allen Mag(338 RUM based) has more capacity then a full length 7mm RUM case because of its improved case design.
That said, if I put the same configuration on the 7mm RUM, the longer case will provide an increase in capacity over the shorter length case.
The limiting factor here is the magazine box length. If we are limited to say a 3.675" OAL. The only way to increase powder capacity once you have improved the case design to the limit is to put more powder capacity around and up the bullet body. This means pushing the shoulder forward so that there is less bullet sticking out of the case.
Do not look at this as seating the bullet deeper into the case capacity because you are not. You are fixed to the 3.675" OAL, all you are doing is pushing the powder capacity up around the bullet to increase it without increasing over all length of the loaded round.
Well, if that maked any sense, feel free to reply!!!
Have a good one,
Kirby Allen(50)
Please explain something to me if you will. I may have been breathing to many fumes from the lathe so bare with me /ubbthreads/images/graemlins/grin.gif!
If you take two cases, both using a 300 gr SMK 338 bullet.
Both seated to the same 3.675" oal.
IF you take the two cases and give them both the exact same shoulder configuration and shoulder diameter, But have one case that has a case body length and case length .100" longer then the other one, How exactly does the shorter case have more volume?
A perfect example of this is my 270 Allen Mag. The original design was based on the 338 RUM case with very similiar case dimensions as what you listed you want in your 338 Thunber(good design by the way /ubbthreads/images/graemlins/grin.gif!!)
Based on the 338 RUM case, the original 270 Allen Mag formed case would hold on average 118 gr of WC872 when filled to the case mouth. This was an average of 10 cases.
In testing I quickly discovered the the 270 bore diameter could easily handle more case volume with the heavy bullets and forming out of the longer 7mm RUM cases was simplistic to the extreme so I redesigned the reamer and tested the new 270 Allen Mag design based on the 7mm RUM. From the Shoulder/case body juntion, the two designs were identical to the case mouth. Shoulders were identical in angle and diameter and the case necks were also identical in length. Only difference was that the 7mm RUM based 270 Allen Mag had a 0.090" longer case body then the 338 RUM based version.
In measuring the same number of 10 cases with the new 270 AM design, the case capacity when filled with the same WC872 to the case mouth had increased to 126 gr.
So given the case shoulder and necks volumes are identical, the longer case will have 8.0 gr more capacity then the shorter case design.
Now rememeber that bullet seating location is unchanged, both are seated to an over all length of 3.675" to feed through the Rem 700 mag box. Since the longer case provides more case volume AROUND the bullet and farther up the bullet, it offers more capacity over the shorter version of the 270 Allen Mag. It also added roughly 100 fps more velocity potential as well.
This pic shows the difference between the 257 Allen Mag(left), original 270 Allen Mag based on the 338 RUM(middle) and the final design of the 270 Allen Mag based on the longer 7mm RUM case.
You can see that all three are loaded to the same 3.675" oal to feed through the Rem 700 receiver but it is clear why the 7mm RUM based 270 AM offers more capacity then the 338 RUM based version.
The 338 RUM and the 338 Edge are exactly in the same boat as the 270 AM. Only real difference is that the Edge has a longer body portion of the case.
That said, with your design, you can match the capacity of the 338 Edge in a shorter case, no arguements from me there. My 257 Allen Mag(338 RUM based) has more capacity then a full length 7mm RUM case because of its improved case design.
That said, if I put the same configuration on the 7mm RUM, the longer case will provide an increase in capacity over the shorter length case.
The limiting factor here is the magazine box length. If we are limited to say a 3.675" OAL. The only way to increase powder capacity once you have improved the case design to the limit is to put more powder capacity around and up the bullet body. This means pushing the shoulder forward so that there is less bullet sticking out of the case.
Do not look at this as seating the bullet deeper into the case capacity because you are not. You are fixed to the 3.675" OAL, all you are doing is pushing the powder capacity up around the bullet to increase it without increasing over all length of the loaded round.
Well, if that maked any sense, feel free to reply!!!
Have a good one,
Kirby Allen(50)
goodgrouper
Well-Known Member
Sounds good Kirby.
My point was that if I were to have a 338 edge made to shoot 225 Ab's and a 338 thunder made to shoot the same bullet, I would recieve about the same case capacity because of the magazine length restriction
even though the thunder is shorter case.
I would tend to think that powder around the bullet would give less capacity than no bullet and pure powder space unless you move the shoulder way forward.
Maybe it won't matter if I just go with a single shot, but I think I would like to have a magazine fed hunting rifle. /ubbthreads/images/graemlins/wink.gif
My point was that if I were to have a 338 edge made to shoot 225 Ab's and a 338 thunder made to shoot the same bullet, I would recieve about the same case capacity because of the magazine length restriction
even though the thunder is shorter case.
I would tend to think that powder around the bullet would give less capacity than no bullet and pure powder space unless you move the shoulder way forward.
Maybe it won't matter if I just go with a single shot, but I think I would like to have a magazine fed hunting rifle. /ubbthreads/images/graemlins/wink.gif
I think what Kirby is trying to say is the only variable you have in both your examples is the shoulder height. <font color="blue">IF</font> OAL stays the same, moving the shoulder forward can only increase case volume. Shoulder placement is the variable now and more is more.
Sounds like your .338 thunder:.338 edge = 300WSM:300 Win Mag in that same (sometimes better) performance in a more compact, improved design. Right track? or too apples
ranges?
Sounds like your .338 thunder:.338 edge = 300WSM:300 Win Mag in that same (sometimes better) performance in a more compact, improved design. Right track? or too apples
ranges?
Fiftydriver
Official LRH Sponsor
GG,
I agree if your design goals were to match the Edge in capacity while allowing more bullet to be outside the case then you designed the Thunder perfectly. I think we are getting on the same page now, to many hours in the shop /ubbthreads/images/graemlins/grin.gif!!
This was the same idea I had with the 257 Allen Mag but to a different degree, while the goal was to get RUM case capacity in the shorter case length, it was also to enable me to chamber the 257 AM in conventional long actions such as the Win 70 standard long action. With the 130 class bullets this is easily accomplished. The big 142s and 156s gr pills are not suitable for these shorter receivers.
Good design, when can we expect holes in targets and critters with the new Thunder??
Kirby Allen(50)
I agree if your design goals were to match the Edge in capacity while allowing more bullet to be outside the case then you designed the Thunder perfectly. I think we are getting on the same page now, to many hours in the shop /ubbthreads/images/graemlins/grin.gif!!
This was the same idea I had with the 257 Allen Mag but to a different degree, while the goal was to get RUM case capacity in the shorter case length, it was also to enable me to chamber the 257 AM in conventional long actions such as the Win 70 standard long action. With the 130 class bullets this is easily accomplished. The big 142s and 156s gr pills are not suitable for these shorter receivers.
Good design, when can we expect holes in targets and critters with the new Thunder??
Kirby Allen(50)
goodgrouper
Well-Known Member
[ QUOTE ]
when can we expect holes in targets and critters with the new Thunder??
[/ QUOTE ]
Well that all depends on how fast you can blueprint and chamber my barrel!! /ubbthreads/images/graemlins/wink.gif /ubbthreads/images/graemlins/grin.gif
In all seriousness, I won't have the barrel ready for a few months because everyone is so backed up. Shilen was the fastest at 3 weeks.
ANy guesses on time frame for Mcmillan to make a left-handed Lazzeroni sporter in marble finish??
Oh, by the way, I just got through breaking in Brian's 284 BSM do-dad whatja ma callit. Excellent work Kirby, I love that finish! /ubbthreads/images/graemlins/wink.gif
when can we expect holes in targets and critters with the new Thunder??
[/ QUOTE ]
Well that all depends on how fast you can blueprint and chamber my barrel!! /ubbthreads/images/graemlins/wink.gif /ubbthreads/images/graemlins/grin.gif
In all seriousness, I won't have the barrel ready for a few months because everyone is so backed up. Shilen was the fastest at 3 weeks.
ANy guesses on time frame for Mcmillan to make a left-handed Lazzeroni sporter in marble finish??
Oh, by the way, I just got through breaking in Brian's 284 BSM do-dad whatja ma callit. Excellent work Kirby, I love that finish! /ubbthreads/images/graemlins/wink.gif
Fiftydriver
Official LRH Sponsor
GG,
Lilja will get you a 338 blank in 8 weeks....
I am booked to my ears until big game season so I would have to wait until after that to get you in, sorry!!!
Course, if you get your barrel from someone, let me know, maybe some late weekend nights may produce what your looking for. Thats kind of how I got Brians rifle finished up.
By the way, how is it shooting?? I hate to ship a rifle out without range testing, like to see those quality groups before shipping but I suspect the rifle is in good hands with any of the crew down there!!
Later,
Kirby Allen(50)
Lilja will get you a 338 blank in 8 weeks....
I am booked to my ears until big game season so I would have to wait until after that to get you in, sorry!!!
Course, if you get your barrel from someone, let me know, maybe some late weekend nights may produce what your looking for. Thats kind of how I got Brians rifle finished up.
By the way, how is it shooting?? I hate to ship a rifle out without range testing, like to see those quality groups before shipping but I suspect the rifle is in good hands with any of the crew down there!!
Later,
Kirby Allen(50)
goodgrouper
Well-Known Member
I hear ya.
I will really start getting it together from November thru January probably.
I was just breaking her in today without a scope even on it, but it cleaned up real nice and I got pretty good at hitting boulders at 300 yards without any sights!
I posted some pics of the break in over on equipment reviews. /ubbthreads/images/graemlins/wink.gif
I will really start getting it together from November thru January probably.
I was just breaking her in today without a scope even on it, but it cleaned up real nice and I got pretty good at hitting boulders at 300 yards without any sights!
I posted some pics of the break in over on equipment reviews. /ubbthreads/images/graemlins/wink.gif
GoodGrouper,
How much is your .338Thunder expected to weigh? I'm really interested in that project of yours. I have been thinking of having a .270AM built in that same configuration except right handed. Do you have experience with the Christensen barrels? Did you check out that other company doing carbon wrapped barrels? I think they use Mike Rock blanks. I've been told by a number of gunsmiths that the carbon wrapped barrels don't work well..
I can't wait to see the completed project. Keep us up to date. /ubbthreads/images/graemlins/cool.gif
How much is your .338Thunder expected to weigh? I'm really interested in that project of yours. I have been thinking of having a .270AM built in that same configuration except right handed. Do you have experience with the Christensen barrels? Did you check out that other company doing carbon wrapped barrels? I think they use Mike Rock blanks. I've been told by a number of gunsmiths that the carbon wrapped barrels don't work well..
I can't wait to see the completed project. Keep us up to date. /ubbthreads/images/graemlins/cool.gif
goodgrouper
Well-Known Member
It should weigh about as much as a regular old BDL remmy or just a few ounces less.
Yes, I have worked with many Christensen barrels and strictly talking about the barrels, they are fine providing that you get the custom barrel that you send them returned.
I have found them to be stiff and accurate, but the main reason I am going with one on this project is barrel heating issues. They cool off much quicker in my experience and that was a problem with the last 338 ultra I did load development for. I shot two shots and it really needed to cool before the third shot and that was on a 50 degree day!
[ QUOTE ]
Did you check out that other company doing carbon wrapped barrels?
[/ QUOTE ]
No. Who are they?
[ QUOTE ]
I've been told by a number of gunsmiths that the carbon wrapped barrels don't work well..
[/ QUOTE ]
I have heard this too but I have seen many many 1/4" groups come from them after a little tlc was applied to the bedding and inletting. Another thing gunsmiths don't like is the amount of barrel shank afforded by their wrapping. It doesn't leave much room for error and there isn't any room to set the barrel back and rechamber when the time comes. I have already talked to Christensen's about this and they agreed to leave me as much shank as I want before the wrap starts. I think I am going to leave about 4 inches of steel before the wrap. That way I can set the barrel back 3-4 times before the whole thing is scrapped. /ubbthreads/images/graemlins/smirk.gif
Yes, I have worked with many Christensen barrels and strictly talking about the barrels, they are fine providing that you get the custom barrel that you send them returned.
I have found them to be stiff and accurate, but the main reason I am going with one on this project is barrel heating issues. They cool off much quicker in my experience and that was a problem with the last 338 ultra I did load development for. I shot two shots and it really needed to cool before the third shot and that was on a 50 degree day!
[ QUOTE ]
Did you check out that other company doing carbon wrapped barrels?
[/ QUOTE ]
No. Who are they?
[ QUOTE ]
I've been told by a number of gunsmiths that the carbon wrapped barrels don't work well..
[/ QUOTE ]
I have heard this too but I have seen many many 1/4" groups come from them after a little tlc was applied to the bedding and inletting. Another thing gunsmiths don't like is the amount of barrel shank afforded by their wrapping. It doesn't leave much room for error and there isn't any room to set the barrel back and rechamber when the time comes. I have already talked to Christensen's about this and they agreed to leave me as much shank as I want before the wrap starts. I think I am going to leave about 4 inches of steel before the wrap. That way I can set the barrel back 3-4 times before the whole thing is scrapped. /ubbthreads/images/graemlins/smirk.gif
Goodgrouper,
Wow that doesn't weigh much for what your getting I think.. The company I am thinking of is Advanced Barrel Systems http://home.alltel.net/mdegerness/
I can't wait to see how yours turns out.. Heck I'd drive out to Utah just to look at it..
Wow that doesn't weigh much for what your getting I think.. The company I am thinking of is Advanced Barrel Systems http://home.alltel.net/mdegerness/
I can't wait to see how yours turns out.. Heck I'd drive out to Utah just to look at it..
goodgrouper
Well-Known Member
[ QUOTE ]
The company I am thinking of is Advanced Barrel Systems
[/ QUOTE ]
Thanks for the link. I checked them out and will definetly be giving them a call. They will wrap a barrel for less then CHristensen.
[ QUOTE ]
can't wait to see how yours turns out.. Heck I'd drive out to Utah just to look at it..
[/ QUOTE ]
Well no need to do that, I will post many pics here when it is completed I am sure. But if you are out this way.........you're more than welcome to slobber on it! /ubbthreads/images/graemlins/wink.gif
The company I am thinking of is Advanced Barrel Systems
[/ QUOTE ]
Thanks for the link. I checked them out and will definetly be giving them a call. They will wrap a barrel for less then CHristensen.
[ QUOTE ]
can't wait to see how yours turns out.. Heck I'd drive out to Utah just to look at it..
[/ QUOTE ]
Well no need to do that, I will post many pics here when it is completed I am sure. But if you are out this way.........you're more than welcome to slobber on it! /ubbthreads/images/graemlins/wink.gif
Goodgrouper,
Yeah I forgot to mention that I thought they did it for less than Christensen. Well we'll see after you post the pics.. I just might have to drive out and see it. I love the look of that Lazzeroni stock but dont know how functional it would be for me. The fact that you like it and are using it says a lot for me. You know your stuff so I figure if you chose this stock for your long range hunting it should do the trick. Thanks for the invite. I'll be waiting to see the results. Thanks again.
Yeah I forgot to mention that I thought they did it for less than Christensen. Well we'll see after you post the pics.. I just might have to drive out and see it. I love the look of that Lazzeroni stock but dont know how functional it would be for me. The fact that you like it and are using it says a lot for me. You know your stuff so I figure if you chose this stock for your long range hunting it should do the trick. Thanks for the invite. I'll be waiting to see the results. Thanks again.
goodgrouper
Well-Known Member
[ QUOTE ]
I figure if you chose this stock for your long range hunting it should do the trick.
[/ QUOTE ]
Well, I confess. I mostly chose the stock because I think it is pretty mean looking and gives good aggressive lines to the rather boring stocks on the rack today. But it is also designed to whisk away the recoil in several different ways which will be a good thing especially if I decide to shoot 250 grain bullets at 3100 fps!
That stock also has a fairly wide forend which I like for sandbags, bipods and varmint rests. It is reported to be 1 7/8" wide.
Oh, by the way, I talked to a "Mike" at ABS today for about 45 minutes and was REALLY impressed with his knowledge and his politeness. As it turned out, I called him right in the middle of a big project and he actually excused himself while he turned off his machines so he could hear me better. I asked him probably 50 questions or so, and he answered them all very well and didn't try to shoo me off the phone. Very cool guy.
I think that I will probably go with his barrel even though I live an hour from the CHristensen arms factory because of two main reasons.
The first reason makes perfect sense. ABS barrels are not about lightness as much as they are about heat dissipation. ABS uses an entirely different carbon wrap with a different applicator process which wics away the heat much more efficiently according to Mike. This property is going to be more important to me than lightness due to the large amount of powder being burned and my serious distrust of barrel burners.
The second reason is application process winds the carbon up with less stress to the barrel so it will finish straighter. Sounds logical to me.
He also said that he would have automaticly left me 4-5" of barrel shank before the wrap started because he knows that people are going to want to set their barrels back and rechamber several times and don't want to pay for a wrap every time.
Anyway, a carbon barrel should be a new angle to experiment with!
I figure if you chose this stock for your long range hunting it should do the trick.
[/ QUOTE ]
Well, I confess. I mostly chose the stock because I think it is pretty mean looking and gives good aggressive lines to the rather boring stocks on the rack today. But it is also designed to whisk away the recoil in several different ways which will be a good thing especially if I decide to shoot 250 grain bullets at 3100 fps!
That stock also has a fairly wide forend which I like for sandbags, bipods and varmint rests. It is reported to be 1 7/8" wide.
Oh, by the way, I talked to a "Mike" at ABS today for about 45 minutes and was REALLY impressed with his knowledge and his politeness. As it turned out, I called him right in the middle of a big project and he actually excused himself while he turned off his machines so he could hear me better. I asked him probably 50 questions or so, and he answered them all very well and didn't try to shoo me off the phone. Very cool guy.
I think that I will probably go with his barrel even though I live an hour from the CHristensen arms factory because of two main reasons.
The first reason makes perfect sense. ABS barrels are not about lightness as much as they are about heat dissipation. ABS uses an entirely different carbon wrap with a different applicator process which wics away the heat much more efficiently according to Mike. This property is going to be more important to me than lightness due to the large amount of powder being burned and my serious distrust of barrel burners.
The second reason is application process winds the carbon up with less stress to the barrel so it will finish straighter. Sounds logical to me.
He also said that he would have automaticly left me 4-5" of barrel shank before the wrap started because he knows that people are going to want to set their barrels back and rechamber several times and don't want to pay for a wrap every time.
Anyway, a carbon barrel should be a new angle to experiment with!
