270 WSM - 170 gr EOL Berger load development

JTB

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Jul 27, 2016
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AZ
i have been working up a load for my M70 270 WSM using the Berger 170gr EOL bullets and just wanted to give a quick report. We finally had a great calm day so I spent an afternoon seeing how the bullets would perform out to 2000 yards. I had previously identified an accurate load utilizing 67.2gr of Retumbo, bullet seated .015" off the lands (overall lengths 3.115"). This loads will just fit in the magazine with a little modification. The bullets are HBN coated with a muzzle velocity of 3050 fps fired through a 26" 1:8 twist barrel. As a terminal reference this load carries 1000 ft-lbs of energy at 1300 yards. I zeroed the load at 300 yards and ended up with 1.25" grouping. The Mark 4 sits atop a 30 MOA base allowing it to be dialed to 2000 yards. Using the shooter app for a starting point I identified/confirmed the following elevation adjustments: 3.1 mil @ 750 yards; 4.8 mil @ 955 yards; 7.1 mil @ 1200 yards; 19.6 mil @ 2000 yards. I confirmed these elevation adjustments with 2 consecutive hits on 18" steel plates at each of the above distances. I only took one shot at the 2000 yard plate but got the hit; didn't want to ruin a good afternoon with a miss at that point. Will need another calm afternoon to see how it will group at 1000 yards. I have yet to try the bullet on large game but it looks like the potential is there for those wanting to reach out with a .277. This turned out to be an amazingly consistent rifle/load.
 

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JTB, just finished a phone conversation with a gunsmith on a new barrel for my .270 Wby going to 1:8. After reading your thread looks like it does quite well. Was wondering if the 1:8 would work with the 150 VLD if I wanted another load besides the 170's. The 170 will be primary.
 
JTB, just finished a phone conversation with a gunsmith on a new barrel for my .270 Wby going to 1:8. After reading your thread looks like it does quite well. Was wondering if the 1:8 would work with the 150 VLD if I wanted another load besides the 170's. The 170 will be primary.

Not to hijack the thread...:)

However, if you are using the stock 270 Wby Mark V action, see if your gunsmith can modify your bolt stop and mag box to get a cartridge (COAL) of at least 3.5" (for the 170 Berger). The stock 270 Wby mag box you can only get to about 3.4" COAL.
 
Thanks 32, I'm now debating chambering to 6.5/300 Wby since I can get a barrel sooner and thought I'd try something different. Had the .270 Wby quite a while.
 
JTB, just finished a phone conversation with a gunsmith on a new barrel for my .270 Wby going to 1:8. After reading your thread looks like it does quite well. Was wondering if the 1:8 would work with the 150 VLD if I wanted another load besides the 170's. The 170 will be primary.

Dosh
I have only tried the 170gr, 150 LR Accubond and 130 gr Berger classic hunter. 130 gr bullet seemed to function about the same as it did with the factory 1:10 twist. If you are interested in shooting the 150gr LR Accubond it performed much better for me with the 1:8 twist; I could not find an accurate load with 1:10. I would expect the 150 VLD to do well with a 1:8 twist
 
Thanks 32, I'm now debating chambering to 6.5/300 Wby since I can get a barrel sooner and thought I'd try something different. Had the .270 Wby quite a while.

Then you will have the best of both worlds...your mag box will be about 3.7" long. Then get a barrel bolt on your 6.5/300 Wby and then you can shoot the 270 Wby when your barrel arrives...:)

Shooting a 170 Berger, with RL26, 3.5 COAL, 28"barrel, 270 Wby @ 3225fps...

Again, sorry for the tread hijack...
 
I rebarreled my Tikka T3 lite with a 1:8 twist barrel and starting handloading the 170 grain Bergers. Finicky as heck but after 60 or so shots of barrel break in and a few different powders I found a sweet spot with 67.6 grains of Retumbo, CCI 250 magnum primers, 2980 fps out of my match grade barrel. Basically jammed they are 0.010 off the lands and if you go 0.050 they scatter all over the place so you have to constantly caliper and double check each and every round. I bought the super slick Forster Bench Rest Ultra Micrometer seater die and that helps out a ton! But every bullet is a hair different so I still hand check each and every one. Got up to 3050 fps with Reloader 26 but accuracy wasn't as good (1.5 MOA) so I went with the slower Retumbo. 0.4 moa at 100, 0.5 moa at 300, 0.5 at 900 yards and that is as far as I've shot it on paper so far. I did shoot an orange (yeah the fruit) at 500 yds last week first shot so I can't complain. Rifle is deadly accurate. I haven't removed the bolt stop and used a longer magazine so I have to hand feed them single shot but man they can shoot!! Killed a blacktail buck and an elk this year with the Berger's and while it was pretty messy on the poor little blacktail, it worked really well on the elk. Passed right through as a matter of fact after blowing the heart in half and hitting 2 ribs. Not too much bloodshot meat and lawnchaired the elk on the spot at 330 yards. I'll save them for specific needs but am going to try and shoot 130's & 140's in copper until I find a combination that matches the same point of impact or really close so I can shoot the copper bullets for 0 to 400 yards and the Berger for 400 yards and out. I don't shoot big game animals past 500 yards but I do practice on paper and steel out to 1300 yards.
 
I rebarreled my Tikka T3 lite with a 1:8 twist barrel and starting handloading the 170 grain Bergers. Finicky as heck but after 60 or so shots of barrel break in and a few different powders I found a sweet spot with 67.6 grains of Retumbo, CCI 250 magnum primers, 2980 fps out of my match grade barrel. Basically jammed they are 0.010 off the lands and if you go 0.050 they scatter all over the place so you have to constantly caliper and double check each and every round. I bought the super slick Forster Bench Rest Ultra Micrometer seater die and that helps out a ton! But every bullet is a hair different so I still hand check each and every one. Got up to 3050 fps with Reloader 26 but accuracy wasn't as good (1.5 MOA) so I went with the slower Retumbo. 0.4 moa at 100, 0.5 moa at 300, 0.5 at 900 yards and that is as far as I've shot it on paper so far. I did shoot an orange (yeah the fruit) at 500 yds last week first shot so I can't complain. Rifle is deadly accurate. I haven't removed the bolt stop and used a longer magazine so I have to hand feed them single shot but man they can shoot!! Killed a blacktail buck and an elk this year with the Berger's and while it was pretty messy on the poor little blacktail, it worked really well on the elk. Passed right through as a matter of fact after blowing the heart in half and hitting 2 ribs. Not too much bloodshot meat and lawnchaired the elk on the spot at 330 yards. I'll save them for specific needs but am going to try and shoot 130's & 140's in copper until I find a combination that matches the same point of impact or really close so I can shoot the copper bullets for 0 to 400 yards and the Berger for 400 yards and out. I don't shoot big game animals past 500 yards but I do practice on paper and steel out to 1300 yards.
I hope you aren't measuring to the tip of the bullets? As opposed to the ogive with a comparator
 
No I haven't tried that yet thanks for the advice.
Sweet you fellas are discussing longrange 270 WSM and 270 WBY projects. Starting a new build for desert Mule deer with a old Sako magnum action and just can't make my mind up on WSM or WBY. Keep the info coming thank you.
 
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