I checked the twist today and was shocked.

[dtknowles]

I bought a used bench rest rifle in 30 BR and had been playing around with it and it never shot as good as I thought is should. I bought it to shoot cast bullets but it did not even shoot quality jacketed bullet at less than 1/2 moa. I thought it might be a brass problem as I was using brass that came with the rifle that were formed from R-P 300 Savage. I have been working to produce some new brass from Lapua 6.5 x 47 brass and in the process I was cleaning the rifle and decided to measure the twist rate. I was sure it was something like 1-16 or 1-18 and needed light bullets as that was what I would have chosen but the measured twist was 1-10. I was shocked. I am going to try and make this barrel work but that means more recoil than necessary.

[Ozark mike]

Why does it mean more recoil. Just try a heavier bullet and see if it likes that. Sounds like small bullets with to high of a rpm

[dtknowles]

Yes, light bullet at too high an rpm. Heavier bullet means more recoil. I don't know if you have shot a 30 bench rest rifle, free recoil it hurt enough with light bullets.

[Ozark mike]

Just a thought Run bigger bullets slower

[B R Shooter]

A 10 twist 30BR is nutz, either it was a set-back barrel or had a specific use in mind when made. On the brass, do yourself a favour and make brass from Lapua 6BR brass. The chamber probably has a tight neck so neck turning will be needed.

[dtknowles]

A 10 twist 30BR is nutz, either it was a set-back barrel or had a specific use in mind when made. On the brass, do yourself a favour and make brass from Lapua 6BR brass. The chamber probably has a tight neck so neck turning will be needed.

I actually bought 6BR brass and it was too short. My chamber is 30 BR long. I fire formed one piece of the 6BR brass in my rifle and it came out with no neck. Yes, I am neck turning. I sold the other 99 pieces of 6 BR brass to a member here and bought the 6.5 x 47 brass which is working out OK.

Here is a thread about my case forming. Pictures of the brass is near the end of the first page of posts.

http://castboolits.gunloads.com/show...-a-Lyman-M-die

Tim

[dtknowles]

A 10 twist 30BR is nutz, either it was a set-back barrel or had a specific use in mind when made. On the brass, do yourself a favour and make brass from Lapua 6BR brass. The chamber probably has a tight neck so neck turning will be needed.

I actually bought 6BR brass and it was too short. My chamber is 30 BR long. I fire formed one piece of the 6BR brass in my rifle and it came out with no neck. Yes, I am neck turning. I sold the other 99 pieces of 6 BR brass to a member here and bought the 6.5 x 47 brass which is working out OK.

Here is a thread about my case forming. Pictures of the brass is near the end of the first page of posts.

http://castboolits.gunloads.com/show...-a-Lyman-M-die

Tim

[B R Shooter]

Tim, the 30BR is the #2 benchrest cartridge in this country, second only to the 6PPC. The 30BR is used almost exclusively in every score shoot for the IBS and NBRSA. There are literally tens of thousands of 30BR rounds shot each year, countless barrels chambered. Unless there is an oldball reamer being made, every one of these rifles use 6BR brass. To make the brass is fairly simple, a couple neck-up steps using mandrels to 30 caliber, then neck turn and fireform. The brass will come out a little over 1.500", which works well as is. There are several people how will make brass for you (do all the work ready to shoot), and they all use 6BR Lapua brass.

[dtknowles]

Tim, the 30BR is the #2 benchrest cartridge in this country, second only to the 6PPC. The 30BR is used almost exclusively in every score shoot for the IBS and NBRSA. There are literally tens of thousands of 30BR rounds shot each year, countless barrels chambered. Unless there is an oldball reamer being made, every one of these rifles use 6BR brass. To make the brass is fairly simple, a couple neck-up steps using mandrels to 30 caliber, then neck turn and fireform. The brass will come out a little over 1.500", which works well as is. There are several people how will make brass for you (do all the work ready to shoot), and they all use 6BR Lapua brass.

The gun is not 30 BR it is 30 BR Long. That is what the die box is marked. Necked up 6BR brass is too short. It could be an oddball reamer. Did you go see my thread on forming and neck turning the Brass? I have made enough brass to know what is required. I also have a 6mm PPC that I got first.

When I got the 6mm BR brass the first thing I did was compare it to the brass that came with the gun that I have used with the gun with both cast and jacketed bullets. The 6mm BR brass was obviously shorter. I was considering that maybe I could use it so I put primed a piece of the 6mm BR brass, charged with some fast powder, topped the filler and a wax plug and fired it. The fireformed case had barely a noticeable neck. Like I said before I sold the rest of that brass and bought 6.5 x 47 Lapua brass, it is the same length as my 30 BR Long brass and is making fine cases. I should have checked the dimensions of 6mm BR before I order the brass, it would have been obvious that it would not work. I thought like you that it was the right parent case for 30 BR and it is but my gun is not 30 BR but 30 BR Long. I took a small loss on the 6mm BR brass, not a big deal mostly just the cost of shipping times two.

This thread is not about making cases, I have that licked. This thread is about the silly fast twist rate. Now I know why I got this rifle so cheap.

Tim

[dtknowles]

Just a thought Run bigger bullets slower

It is a good thought, I will run the heavy bullets slower.

[B R Shooter]

A friend/shooting buddy and me made up an "improved" 30BR, since after shooting the regular 30BR for so long and trying to stuff more and more powder in, we improved it by moving the shoulder forward .075" and shortening the neck. We thought it worked much better, he still shoots it today, I don't shoot a 30 in score anymore. But that's not what you have, you have a real time longer case BR. Wonder why they did that? Sorry for the confusion.

[dtknowles]

No problem thanks for sticking around. Why don't you shoot a 30 in score, you change guns or stop shooting score?

I don't compete. I got the 6mm PPC because I want to see if the reason I was not shooting tiny groups was it me or the guns I was shooting. I was able to shoot groups under 0.250 MOA with that gun. Not competitive but more than twice as good as anything else I had ever shot. I just never had a rifle capable of under 0.500 MOA so no matte how hard I tried it was just not happening but I wondered if I was the weak link. Now I know that at most I contribute 0.250 to my group sizes when I really try.

I got the 30 BR that turned out to be a 30 BR Long to see if I could shrink my cast bullet group sizes. I really want to shoot cast bullets to less than 1.00 MOA. I really think this is possible and the new brass way just another step in getting there.

Tim

[dtknowles]

........But that's not what you have, you have a real time longer case BR. Wonder why they did that? Sorry for the confusion.

I think this gun was built for a longer range game than 100 or 200 yards. More powder and heavier bullets to means more range.

Tim

[B R Shooter]

I think this gun was built for a longer range game than 100 or 200 yards. More powder and heavier bullets to means more range.

Tim

You are probably right, but it really shouldn't have been marked as a 30BR. The same go-gauge is to be used on every "BR" case, from 22, 6mm, 25, 6.5mm, 7mm and 30.

[dtknowles]

You are probably right, but it really shouldn't have been marked as a 30BR. The same go-gauge is to be used on every "BR" case, from 22, 6mm, 25, 6.5mm, 7mm and 30.

The gun is not mark buy caliber or maker, just a window cut in the sleeve to show the serial number on the receiver. I don't have a copy of the auction and the sales receipt is not close at hand but I thought I was buying a 30 BR and I never asked about the twist. It came with dies and brass so I loaded and shot it trying to get the accuracy I expected and was thinking maybe it was shot out. Now I am thinking I was just shooting the wrong bullets. Instead of 120 gr. bullets I should be shooting 150 or 180 gr bullets.

Tim

[dtknowles]

Some of my cast bullet groups

[303Guy]

In my ignorance, if I may ask, would it not be the throat cut to accommodate heavier and thus longer bullets that is the cause of the lighter bullets not shooting well? Or is it purely excessive twist rate? I ask for my own education.

[Texas by God]

Nice rifle! I'd like to see a 30 BR long next to a regular 30 BR if you have a pic. I'm not a bench shooter, but I do have two 10" twist .30 cal rifles that shoot 150 to 180 gr boolits very well.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[dtknowles]

In my ignorance, if I may ask, would it not be the throat cut to accommodate heavier and thus longer bullets that is the cause of the lighter bullets not shooting well? Or is it purely excessive twist rate? I ask for my own education.

I had the same thought but even the lighter bullets are engaging the rifling when chambered. This gun has almost no leade or throat. Maybe 0.025" from the case mouth to the start of the rifling.

I have learned that when you buy a used custom rifle from an online auction, you might get some surprises.

Tim

[dtknowles]

Nice rifle! I'd like to see a 30 BR long next to a regular 30 BR if you have a pic. I'm not a bench shooter, but I do have two 10" twist .30 cal rifles that shoot 150 to 180 gr boolits very well.

Sent from my SAMSUNG-SM-G930A using Tapatalk

This is photo shopped but is pretty close



Tim