New stock 180 Hybrids vs. old

[Cakes]

I've been using an old lot of 180 hybrids for many years (lot# 4682) and they have served me quite well. Down to the last 600 so I ordered some "new" ones (lot# 9280). They definitely shoot different (unfortunately for the worse) have a bit longer tip to ogive and I noticed Berger has upped the G1 from .674 to .680 with a new optimal twist rate now of 1:8 vs the old standard of 1:9. I've shot 9 twist with my straight .284 forever and curious if this is the root cause for the lowered performance? Comments/thoughts please. Eric in DL

 

[TAJ45]

Have recently started a mental info dump abt the .284 and 7mm pills. One post, maybe mfr hints listed 9tw as being just in the OK zone for 180s whereas several above avg competitors say different. Mebbe like the 12 tw in a 20 not handling the 40s and some say no problem. It seems ive read where going back and frth twixt VLDs and Hybrids in the 6s, didnt give great results.
So maybe that is your case?
If I would start from scratch, I'd do an 8.5 for insurance, if not an 8.25. But what I don't know would fill several Amazon warehouses.

 

[clowdis]

Admire anyone who can get accuracy and 2900 fps out of a .284 using a 180 grain bullet. Mine is only running about 2785 with Sierra 175's or Berger 180's. Anything higher and the accuracy goes to crap.

 

[Baka]

I've been using an old lot of 180 hybrids for many years (lot# 4682) and they have served me quite well. Down to the last 600 so I ordered some "new" ones (lot# 9280). They definitely shoot different (unfortunately for the worse) have a bit longer tip to ogive and I noticed Berger has upped the G1 from .674 to .680 with a new optimal twist rate now of 1:8 vs the old standard of 1:9. I've shot 9 twist with my straight .284 forever and curious if this is the root cause for the lowered performance? Comments/thoughts please. Eric in DL

Cakes just send me the bullets and I'll dispose of them for you. There problem solved!

 

[Steve Blair]

Admire anyone who can get accuracy and 2900 fps out of a .284 using a 180 grain bullet. Mine is only running about 2785 with Sierra 175's or Berger 180's. Anything higher and the accuracy goes to crap.

A .284 Win with 32" barrel should tune ~2820. My Shehane with 32" barrel tunes ~2930-2940 with 180 Hybrids. I had one Krieger that ran ~2965 with .2 grains less powder, but that was just a fast barrel. The next one was back to 2930-2940.

 

[clowdis]

A .284 Win with 32" barrel should tune ~2820. My Shehane with 32" barrel tunes ~2930-2940 with 180 Hybrids. I had one Krieger that ran ~2965 with .2 grains less powder, but that was just a fast barrel. The next one was back to 2930-2940.

Mine is a 30" so sounds about right. My "personal opinion" and that's all it is, is that the 175+ bullets are too big for the straight .284. I had a 7RSAUM that just hammered with them but I can't get enough speed out of the .284. Now I have tried some 162 A-maxs and won the last 600 yard match I shot with them so I may see what I can develop using the lighter bullet. JBM calculations say that at 2900 fps it will shoot inside the 175/180 bullets at 1,000 yards and I can get the 2900 with the lighter bullets. I intend to have a go at the new ELR Hornadys as well as the new 161 TMK from Sierra. Should be interesting.

 

[Cakes]

Yes I'd love to get 2900+ out of my .284 also. I suspect the primer pockets would get beat to death pretty quick. I appreciate the comments. I have usually found my node around 2830' for a 30" and straight .284. I was more interested in why Berger changed their rec. twist rate. I realize the different BC is probably an ongoing process of fine-tuning for all bullet companies. I chrono all load development and it appears for me these new ones like 2785' as well. Anyone remember if around 10'/sec per inch is a valid assumption. I had some new barrels chambered and one ended up at 29". Don't know if I'll be able to get that one up to speed. Eric in DL

 

[Corey Schwanz]

This might shed some light on the different BC issue: http://www.bergerbullets.com/update-of-berger-bullets-performance-data/. The bullets have not been altered but the performance data surrounding them have been updated. We also updated some twist rate recommendations to ensure maximum performance from our bullets: http://www.bergerbullets.com/berger-bullets-twist-rate-recommendations-by-eric-stecker-bryan-litz/. The newer twist numbers may be tad faster but are chosen to ensure that shooters can achieve an SG of 1.5 or higher under just about any condition. You can always use the twist rate calculator on the website to plug in your specific variable and see where you stand.

Short version, if you've had a good shooting setup before, no reason to expect anything different now. Lot to lot variation, you may need to tweak the tune slightly to get the same groups, but if the rifle has shot the bullets well in the past, there is no need to run out and get a new barrel right away now.