Loading up a bunch of 7mm-08 for this weekend, went thru one box of 130gr Match 1903. Opened the next box and saw the bullets were longer, they weighed the same +/- .2gr they seated to the same depth thanx to Forster Bonanza die from Mysticplayer but the first box bullet length was 1.134" and the second box was 1.200". Will contact Sierra to find out which batch is the new length and load accordingly. The extra meat goes into the case so I'm sure POI will change, gonna find out sunday.
SMK weird length change.
- Thread starter savagefan
- Start date
rnbra-shooter
CGN Ultra frequent flyer
- Location
- New Brunswick
Sierra HPBTs are pretty variable in length; easily 10 thou variations within the same box, and 20 thou from batch to batch. Though they still shoot great, and for the most part the important part (the shank/ogive junction) gets seated to a pretty consistent place w.r.t. the rifling, by most seater stems.
But, 66 thou difference - wow. Sounds to me like they made a design change to the bullet and didn't tell anybody. If you are talking to a person who sounds clueful, see if you can get a straight up answer whether or not this is what happened.
Oftentimes when a match bullet design changes, they alter the boattail angle and/or length - can you tell if the back part of these two bullets are the same or if they have changed it there?
But, 66 thou difference - wow. Sounds to me like they made a design change to the bullet and didn't tell anybody. If you are talking to a person who sounds clueful, see if you can get a straight up answer whether or not this is what happened.
Oftentimes when a match bullet design changes, they alter the boattail angle and/or length - can you tell if the back part of these two bullets are the same or if they have changed it there?
6mm Shooter
CGN Regular
- Location
- White City, SK
Sounds like you guys that were flaming Berger and praising Sierra need to eat a little crow.
Here's the answer I received today. For the record at 100 yards there was no difference in P.O.I.
Thank you for the e-mail.
There hasn't been a length change made to the #1903 bullets and I am hard pressed to give you an explanation as to how we managed to get .066" difference in bullet length except to say that as lubrication amounts vary so will the finished bullet length. This occurs when you have a jacket with less lubrication that is formed into a bullet and the result is a slightly short bullet but when a slightly "wet" jacket is formed into a bullet the result will be slightly longer than norm. As you pointed out the ogives are the same but the bearing surface will be slightly different even though they came out of the same dies and machine. While this does change the internal capacity slightly there are no safety issues involved. There could be some long range accuracy differences bullet to bullet but at 200 yards or less I doubt if the differences can be shot because obviously they pass our stringent quality control standards of 10 shots inside 1.250" at 200 yards.
That's the best I've got. Do you have any questions.
Rich
Thank you for the e-mail.
There hasn't been a length change made to the #1903 bullets and I am hard pressed to give you an explanation as to how we managed to get .066" difference in bullet length except to say that as lubrication amounts vary so will the finished bullet length. This occurs when you have a jacket with less lubrication that is formed into a bullet and the result is a slightly short bullet but when a slightly "wet" jacket is formed into a bullet the result will be slightly longer than norm. As you pointed out the ogives are the same but the bearing surface will be slightly different even though they came out of the same dies and machine. While this does change the internal capacity slightly there are no safety issues involved. There could be some long range accuracy differences bullet to bullet but at 200 yards or less I doubt if the differences can be shot because obviously they pass our stringent quality control standards of 10 shots inside 1.250" at 200 yards.
That's the best I've got. Do you have any questions.
Rich
