Fiftydriver
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Richard Graves has come up with a 17 cal bullet that may well take the long range performance of this caliber to 2 to 3 times what it is currently limited to.
This pic shows two moly coated 20 gr V-Max bullets on the left and two 45 gr ULD RBBTs on the right.
Richard has ordered a test rifle for this bullet which he will be using as his calling rifle for hunting yotes up north. I will not give the details of this rifle because he kind of put it in my hands and I want to keep it a suprise from him but I can give you some general specs of the rifle.
With a bullet this large you need a pretty significant engine to drive them. We talked several rounds over and even considered developing a 17 Allen Mag but to be honest there are alot of 17 cals out there. We talked about using the PPC and BR cases but decided they were really more then needed with the 17 cal bore even with these bullets and powder fouling which is a real problem with any large 17 cal would be more then wanted with these larger cases for the 17.
In the end, we dropped the 17 Allen Mag idea and I just ordered in a 17-223 Ack Improved reamer with a 30 degree shoulder to aid in smooth feeding and to prevent any possible powder bridging issues.
The latter point will probably not be an issue because the powders we will be testing will more then likely be ball powders such as H-BLC2, H-335 and possibly even H-380 along with W-748 and some of the appropriate Ramshot powders which are of course all ball powders.
Mainly the 30 degree shoulder will be for smooth feeding more then anything. This case will have roughly 30 gr of usible powder capacity so it should be perfect for this heavy 17 cal bullet.
The 45 gr ULD RBBT is right at 1" in length which for a 17 cal bullet is significantly longer then even the 37 gr Berger VLD.
The main problem with the VLD bullets in 17 cal is that they are built on VERY thin jacketed bullets and when driven to high velocity in fast twist barrels, they spin apart rather easily.
This will not be the case with this bullet, it is built on a jacket significantly heavier then the J-4 jacket so blow ups should not be as much of a problem, depending on just how fast we can drive them.
BC predictions will be in the .6 range if the projections are accurate. We tend to agree with those numbers from what we have been seeing with the other ULD RBBTs bullets.
The main issue will be which twist to use. We will be using arguably the best 17 cal barrels in the world from Dan Lilja. Dan offers both a 1-7 and 1-6 twist and we will be trying the 1-7 first with this heavy bullet. With the velocity potential of the 17-223 AI I suspect we will get good results from the 1-7 twist. If not, we have the 1-6 to fall back on but I suspect this will not be needed.
I really have no idea what the velocity potential of this chambering with this bullet weight will be. I am hoping to see at least 3400 fps and possibly +3500 fps depending on barrel length but again, there are no standards here so we will see.
barrels, reamers, stocks and all componants are ordered, now we have to hurry up and wait for them to get here. That is good because I have a "few" customers rifles to get out before this big game season!!! /ubbthreads/images/graemlins/grin.gif
Just an update on more things to come!!
Kirby Allen(50)
This pic shows two moly coated 20 gr V-Max bullets on the left and two 45 gr ULD RBBTs on the right.
Richard has ordered a test rifle for this bullet which he will be using as his calling rifle for hunting yotes up north. I will not give the details of this rifle because he kind of put it in my hands and I want to keep it a suprise from him but I can give you some general specs of the rifle.
With a bullet this large you need a pretty significant engine to drive them. We talked several rounds over and even considered developing a 17 Allen Mag but to be honest there are alot of 17 cals out there. We talked about using the PPC and BR cases but decided they were really more then needed with the 17 cal bore even with these bullets and powder fouling which is a real problem with any large 17 cal would be more then wanted with these larger cases for the 17.
In the end, we dropped the 17 Allen Mag idea and I just ordered in a 17-223 Ack Improved reamer with a 30 degree shoulder to aid in smooth feeding and to prevent any possible powder bridging issues.
The latter point will probably not be an issue because the powders we will be testing will more then likely be ball powders such as H-BLC2, H-335 and possibly even H-380 along with W-748 and some of the appropriate Ramshot powders which are of course all ball powders.
Mainly the 30 degree shoulder will be for smooth feeding more then anything. This case will have roughly 30 gr of usible powder capacity so it should be perfect for this heavy 17 cal bullet.
The 45 gr ULD RBBT is right at 1" in length which for a 17 cal bullet is significantly longer then even the 37 gr Berger VLD.
The main problem with the VLD bullets in 17 cal is that they are built on VERY thin jacketed bullets and when driven to high velocity in fast twist barrels, they spin apart rather easily.
This will not be the case with this bullet, it is built on a jacket significantly heavier then the J-4 jacket so blow ups should not be as much of a problem, depending on just how fast we can drive them.
BC predictions will be in the .6 range if the projections are accurate. We tend to agree with those numbers from what we have been seeing with the other ULD RBBTs bullets.
The main issue will be which twist to use. We will be using arguably the best 17 cal barrels in the world from Dan Lilja. Dan offers both a 1-7 and 1-6 twist and we will be trying the 1-7 first with this heavy bullet. With the velocity potential of the 17-223 AI I suspect we will get good results from the 1-7 twist. If not, we have the 1-6 to fall back on but I suspect this will not be needed.
I really have no idea what the velocity potential of this chambering with this bullet weight will be. I am hoping to see at least 3400 fps and possibly +3500 fps depending on barrel length but again, there are no standards here so we will see.
barrels, reamers, stocks and all componants are ordered, now we have to hurry up and wait for them to get here. That is good because I have a "few" customers rifles to get out before this big game season!!! /ubbthreads/images/graemlins/grin.gif
Just an update on more things to come!!
Kirby Allen(50)
