105 Berger hybrid target

[atkins08]

I decided to try 105 berger target hybirds for my 6xc. I first bought a 100 pack that measured 1.675 base to ogive with hornady calipers, and a hornady comparator. I then bought a 500 pack of a different lot number. These measure 1.657 base to ogive with the same caliper and comparator. Is this normal for berger? Seems like a big difference between the two lots.

 

[Zero333]

Yep. That's normal for all bullet brands and makes across the board.

Even Berger.

 

[geo.ulrich]

Yep. That's normal for all bullet brands and makes across the board.

Even Berger.

at least the factory bullets not so much in the custom

 

[atkins08]

The part that really threw me for a loop was when I checked coal again with a hornady oal gauge it only showed .003 difference from the first batch. So .018 difference in my comparator, but only .003 in my chamber. It did change the way the gun grouped. With the first batch at 5 thousands off the lands the gun shot very well and an sd of 3 to 4. With minimal testing with the new batch the groups and sd have opened up significantly. I guess its time for another seating depth test

 

[brxbrad]

I've found that if I maintain the same distance from the lands that I used before changing lots numbers, things stay the same. The bullet still weighs 105grs and if you are still using the same powder and primers then that only leaves harmonics. Same distance, same powder and charge, same primers, same type of bullet and weight, and same measurement to lands for me equals same results.

 

[atkins08]

I've found that if I maintain the same distance from the lands that I used before changing lots numbers, things stay the same. The bullet still weighs 105grs and if you are still using the same powder and primers then that only leaves harmonics. Same distance, same powder and charge, same primers, same type of bullet and weight, and same measurement to lands for me equals same results.

I tried that thinking the same. However my groups opened slightly, but my chrono numbers blew open. The same load was getting me an sd of 3 went to an sd of 12

 

[Ned Ludd]

This is normal and why you always need to do a load re-workup, or at the very least some validation/confirmation that the load is performing acceptably, after changing any component Lot #, including brass, primers, bullets, or powder.

 

[brxbrad]

I tried that thinking the same. However my groups opened slightly, but my chrono numbers blew open. The same load was getting me an sd of 3 went to an sd of 12

You said slightly....can you elaborate? Its sounds like you shoot BR. I can see concerns there but my biggest problem over the course of fire is being able to control the wind better than the wind controls me....

 

[spclark]

Is this normal for berger? Seems like a big difference between the two lots.

No, that's typical.

Dies wear, get changed, product varies slightly coming off the press afterwards. Why we try try to buy 500-x,000 at a time from the same lot if possible.

Why when changing lots it's worthwhile checking old vs. new, maybe varying seating depth / jump / jam a little, learn whether there's something a little bit better from the change.

 

[atkins08]

You said slightly....can you elaborate? Its sounds like you shoot BR. I can see concerns there but my biggest problem over the course of fire is being able to control the wind better than the wind controls me....

Basically went from 1/4 moa to half. But honestly the chrono numbers bothered me more. They went crazy, with the last 3 shot group I shot having an es of 40

 

[atkins08]

No, that's typical.

Dies wear, get changed, product varies slightly coming off the press afterwards. Why we try try to buy 500-x,000 at a time from the same lot if possible.

Why when changing lots it's worthwhile checking old vs. new, maybe varying seating depth / jump / jam a little, learn whether there's something a little bit better from the change.

Makes sense. I was about to the end of my 1# of rl16, and getting ready to open my 8# jug so it sounds like a new work up is what is in store.

 

[spclark]

Makes sense. I was about to the end of my 1# of rl16, and getting ready to open my 8# jug so it sounds like a new work up is what is in store.

I certainly would, with a propellant that new on the scene. At least start with a few rounds built same/same as used with the first bottle, see what - if any - changes become evident.

That's how I approached using IMR's new 8208XBR in 6XC when it first came out. I'd bought some thinking it might be worth trying for Palma loads (308WIN, 155 grain bullets; worked great until I found something even better!) but with reports of its burn rate early on being maybe a bit too fast and no reloading data for it in this cartridge, each new batch I bought got careful scrutiny. I iearned not only did it work great with 105-107 grain bullets but it didn't change much at all lot to lot.

I have some RL16 but didn't have time to get it tested with 6XC last year. Be interested in discussing your history with it, whether here in the open or by PM.

 

[brxbrad]

Basically went from 1/4 moa to half. But honestly the chrono numbers bothered me more. They went crazy, with the last 3 shot group I shot having an es of 40

That's a lot. I would ask myself what else changed from the time I tested the first lot to the last. Things like barrel ware, temp at time of testing, powder type and lot #, neck tension due to work hardened brass, does the brass need to be annealed, or maybe a possible glitch with the Chronograph. Noticeable changes for me are usually due to something I did or missed in my process or shooting regimen ....I wonder how Brian Litz would comment on your original post. I agree with buying 500 or more at a time to take that problem out of the equation..

 

[atkins08]

That's a lot. I would ask myself what else changed from the time I tested the first lot to the last. Things like barrel ware, temp at time of testing, powder type and lot #, neck tension due to work hardened brass, does the brass need to be annealed, or maybe a possible glitch with the Chronograph. Noticeable changes for me are usually due to something I did or missed in my process or shooting regimen ....I wonder how Brian Litz would comment on your original post. I agree with buying 500 or more at a time to take that problem out of the equation..

The brass was on its second firing same as some of the original testing. The barrel has just over 100 rounds on it. The chrony could have glitched, but it sure seems like my node changed with the new lot of bullets. The bad thing is that was the last of my 1# jug of powder. Now I'm on an 8# so it really throws another variable in the mix.

 

[brxbrad]

New 8lb jug of powder, new lot of 500 bullets, barrel just broke in, 2nd firing on cases, and same primers. I would forget the old numbers and results and basically start my load development over. Just my opinion...

 

[Liven The Dream]

This is common...
Will give Nosler a High five. New RDF 6.5 140gr. Bullets to different Lot's. only .003 different.
Have not test yet our Range has been Closed ?

 

[Judd]

I had a jug of Varget that I matched speed and attempted to re-tune but never could hit on anything in my dasher. It shot the previous lot but I couldn't get it to shoot this new lot. Nothing was wrong with the powder because I shelved it and then pulled out back out and out shot great out of a brx.

I know it's not bullets but I mention it because every barrel it's different. This is the reason a lot of us buy enough powder and bullets to last a barrel. Good luck!

 

[atkins08]

I had a jug of Varget that I matched speed and attempted to re-tune but never could hit on anything in my dasher. It shot the previous lot but I couldn't get it to shoot this new lot. Nothing was wrong with the powder because I shelved it and then pulled out back out and out shot great out of a brx.

I know it's not bullets but I mention it because every barrel it's different. This is the reason a lot of us buy enough powder and bullets to last a barrel. Good luck!

That makes sense. Live and learn I guess. Hopefully the 8# jug comes in like the first pound. My wife is about to cut me off my gun money after this build!