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LongRange
11-10-2015, 04:21 PM
your not going to give up much...im just a little over 2800 out of a 26" barrel...the hornadys have a longer bearing surface than the 140g hybrids...does QL show the same(or close)pressures between the two bullets?
cowtownup
11-10-2015, 04:57 PM
At the same powder charge of 41.6 grains of H4350..
140 Hybrid = 59,027 psi
140 Amax = 56,580 psi

I run the Amax at 40.8 grains which is 55,770 psi...

I have not found out where the 140 Hybrids work best cause I've not shot any yet, but it will be interesting to see where they land in relation to the Amax..
keeki
11-10-2015, 05:52 PM
If 4350 shoots that well, I'd be giving rl17 a try
LongRange
11-10-2015, 06:55 PM
At the same powder charge of 41.6 grains of H4350..
140 Hybrid = 59,027 psi
140 Amax = 56,580 psi

I run the Amax at 40.8 grains which is 55,770 psi...

I have not found out where the 140 Hybrids work best cause I've not shot any yet, but it will be interesting to see where they land in relation to the Amax..

thats one of the quirks i found with QL...in reality if a bullet has more bearing surface it creates more pressure than a shorter bearing surface...if i remember correctly a 140g hornady has .634 bearing surface(same as a 139g lapua)the 140g bergers are about .573(about the same as a 142g smk)if measured with two comparators...so with the same load the berger should be the lower of the two pressures.
my charge is a little higher than 41.6 with same length barrel and im only 30fps faster than your projected load at 41.6...over pressure? maybe...but my primers are no where near flat yet and i have no hard bolt lift.

id either start at 40g and .015 off the lands with the bergers and work up in .3g increments or set your max charge at 41.5g and run an OCW test at .015 off the lands...the bergers are going to shoot well some where around mid 2700 then again around 2800 then again around 2900...i can run them up to 2920 or so but primers are pretty flat...they also shot very well for me at 2680 to 2720 during firing forming.
rbp75503
11-13-2015, 03:37 PM
Was able to get to the range a second time this week in-between the monsoons. The lapuas and H4350 showed great promise with a .025" jump I reseated my go-to load of N550 at .025" off the lands. And once again that last shot was pulled by some invisible force.:rolleyes:

http://i993.photobucket.com/albums/af56/rbp71854/11-12-2015_260REM-Savage-Shilen_139GR%20Lapua-Scenars-1_zpsuvoc4f76.jpg
LongRange
11-13-2015, 03:45 PM
try .015 and .035 that will tell you if they want more or less jump.
cowtownup
11-13-2015, 03:46 PM
Oh wow.. You have got to be pretty satisfied with that.. I'm still having trouble getting the 140 Hybrids to shoot...
LongRange
11-13-2015, 04:30 PM
Oh wow.. You have got to be pretty satisfied with that.. I'm still having trouble getting the 140 Hybrids to shoot...

what powder primer brass combo are you using.
cowtownup
11-13-2015, 04:32 PM
H4350 - Lapua Brass - FGMM Primers..
LongRange
11-13-2015, 04:33 PM
how about charge weights and seating depths?
rbp75503
11-13-2015, 04:54 PM
try .015 and .035 that will tell you if they want more or less jump.

I have tried .015" off the lands and the groups opened up. I will definitely give .035" a try at next range day.

Cowtownup, I am nearly satisfied, I believe I should be able to get .200" groups consistently with this barrel, if I do my part.
LongRange
11-13-2015, 05:01 PM
I have tried .015" off the lands and the groups opened up. I will definitely give .035" a try at next range day.

Cowtownup, I am nearly satisfied, I believe I should be able to get .200" groups consistently with this barrel, if I do my part.

since you have been closer and .025 looks pretty good you may want to go .030 .035 and .040 just to make sure you dont miss a sweet spot.