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7mm 160 gr tipped matchings

Posted: Sat Jul 01, 2017 8:43 am
by Berger
Anybody using these bullets.thoughts please.ive had one opinion from one of the experts amongst us.just wondering what others opinions are on these bullets.cheers Berger

Re: 7mm 160 gr tipped matchings

Posted: Sat Jul 01, 2017 9:50 am
by Laurie
They are very good Neil. Well made, appear to have a similar BC to the old 162gn Hornady AMax, but being a long-nose tangent ogive design they are much easier to tune COAL-wise than the secant-form AMax. Sierra has really improved its consistency over recent years and the TMKs are good examples of that - a maximum three thou' variation in base to ogive readings and hardly any weight variations. For ballistic programs, I input an estimate of 0.300 G7 BC which appears reasonably close.

I use them in my 7mm-08 F-Class rifle at 2,825 fps and for shorter distance matches in my 284 at ~2,900 fps.

Re: 7mm 160 gr tipped matchings

Posted: Sat Jul 01, 2017 3:09 pm
by Sim G
What powder are you using, Laurie? The fastest I seem to be able to dive 162 A Max's or 168 SMKs is around 2600 using H414. Reloader 19 gave me over 2700 but was not good group wise.

Re: 7mm 160 gr tipped matchings

Posted: Sat Jul 01, 2017 5:37 pm
by Laurie
Viht N160. That's in a very long freebore chamber for optimised seating depth with the Berger 168gn VLD - but which the barrel doesn't like! It's 2 point nine something inches COAL with either the TMK or 162 AMax. 31-inch barrel and just over 47gn N160 in a reformed small primer Lapua 308 Palma case. Pressures aren't high though.

I tried some of the recommended powders from the American forums such as IMR-4007ssc, but they didn't give nearly high enough velocities. To match a 260 Rem / 6.5X47L / Creedmoor shooting a high BC 0.264" 140gn bullet, you really need 2,800 fps or so. I looked at the AI version when I had the rifle rebarrelled, but decided to go for the standard version given the problems a few years back in getting any out of the ordinary dies, as this was in the time of the great US tools and components shortages. With hindsight, doing it again today, I'd definitely go 7-08AI for that useful bit of extra capacity / charge weight.

It performs very well as is though and has got me some good F-Class results in 300-600 yards matches. I shot it in a UKBRA 1,000 yard benchrest match three weeks ago and got a best group of 6.5" with three more in the 'nines' for 6th 'Heavy Gun' and 7th overall so it has the legs with the TMK for this distance. Elevations were superb, the groups being all lateral due to wind effects (and my shooting too slowly). Recoil is very mild in a 20lb rifle and it's pleasant and easy to shoot.

I have a low round count threaded and chambered 6.5X55 barrel that was on this rifle previously ready to go on once the 7mm barrel is shot out so it'll be interesting to see how the 140gn 264 Berger LRBT at the same MV as the 7mm TMK compares.

Re: 7mm 160 gr tipped matchings

Posted: Sun Jul 02, 2017 10:22 am
by Sim G
Thanks for that Laurie, I really appreciate it. 31 inch barrel? I reckon I should be really pleased with my 2600 out of a 23.5" RPA!

I've always regarded it as a 600m rifle anyway and have been playing around with other weights of bullets. My local shop had a stock of 130gn SMKs that I got at a ridiculous discount and spent a very nice morning yesterday just hitting the 2" day glow marker at 300m! With some H4350 I had languishing in the cupboard, it's giving me 2920fps. And moderated its like shooting a .223 sporter!

Re: 7mm 160 gr tipped matchings

Posted: Sat Jul 08, 2017 8:01 am
by Berger
I didn't realise you were shooting these 160gr tmk's at a 1000yds.I looked through the results on ukv.nice shooting Laurie.somebody shot a real nice 4 inch group.I expect you've shot many a 4 inch group yourself Laurie.its a bit late to change my mind on bullet choice now as I've got 1000x180gr Scenar L's

Re: 7mm 160 gr tipped matchings

Posted: Sat Jul 08, 2017 4:39 pm
by Berger
I stumbled on some federal match gold magnum primers today.didnt buy them.gonna try br2s first