Starting a Ladder for T3 7mm Rem Mag with 162gr A-max's

Hi All,

I've managed to collect just under a hundred rounds of Federal and Norma factory brass now, So have set up the Lee reloading station and FINALLY managed to get hold of a box of 162 gr A-max's :omg::omg::D

Previously I've been shooting !50 grain SP Federal Blue factory that groups sub moa on average (about best is .75 inch@100m) and 140 grain TTSX Norma factory (cloverleaf 3 shots happily@ 100 and about .5 MOA average)

So I'm looking to create a ladder for my reloads and testing the load development on the 200m Rage up here in Auckland or at the Farm. I'm using a 7mm Rem Mag T3 lite Suppressed(as that's what I use in the field). and I'll be using Federal Match Primers for the 162grainers in once fired Federal brass and will be using IMR 7828.

Has anyone run exactly the same (or very similar) load development as this so I can compare and decide the start, mid, and top of my trial ladder to reload to. I don't have a chrony at this stage to map the speeds but happy to share info with my results and the advice coming from you guys with experience in such matters.

I'd like accuracy over a group over a speed race guys - so any thoughts? where to start load wise for the A-max?

Best regards
P.

Personally for a Rem mag I'd be looking at 2217 or 2225

The latter being more appropriate.

Quote:

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Originally Posted by Tui4Me

Personally for a Rem mag I'd be looking at 2217 or 2225

The latter being more appropriate.

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Thanks Tui - it was a let's start here call, based on the Hornady ballistics tables I have copied for the a-max. I do have to say so if the consensus is 2225 as being best to use in this situation its unopened so I'm sure Mike can get it swapped for me... I did it based on the following..

Attachment 29996

And this was what the main idea was to attain accuracy of the load for my set up and this seemed to have a nice mild end at 2600 for 55gr going up to 63+ for 2900.

As always open to suggestions...

stick with one lot of brass.. probably the norma

Btw - I fully realise i'll be single feeding this puppy as the a-max's won't sit in the standard magazine. Before someone points out the obvious...

Surely you could seat them to mag fit!

I just run mine at mag length and they go awesome

So you've found Amax don't need to be right up there then?

That's my hope @distant stalker with the IMR 7828 you'll see (from the chart comparison) you potentially don't need quite as much to hit the 2900 mark let alone the 2800. Hope fully that will allow me to seat the projectile a little deeper without compression in a standard Tikka mag. However if it doesn't I know I can go up the ladder and just single load them fine. If I dial back a bit look for the accuracy sweet spot where lets face it Id be happy dropping beasts out to 600 ethically all day long. No need to get into a speed race for ever decreasing returns.

As it is I have to wait awhile between rounds to shoot groups because of the heat generated by the over barrel supressor - but I'm used to that so single feed is not really a issue and maintain optimal cheek weld for consistency with a old hair tie taped to where my cheekbone touches the stock to ensure the same eye relief every time off the bags.

So has anybody shot this config before and can give me a similar sweet spot to start above and below? (i.e a ladder) if not I'm gonna start midway and do .5 grain increases till I see a pattern at 200m.

Good luck mate but like most tikkas it will probably like whatever you give it ;)

I was running 70g of 2217 with an Amax seated at mag length, 85mm from memory. Gave me 2950 fps and shot 0.6 moa.

I mucked about with Amaxs at various seating depths. Got pissed off with it all and seated them to mag length with 72 grains 2217 and they shot like a house on fire. Then I sold the shooter. What a clown..

Thanks @Ginga - sounds like a good place to start...

Quote:

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Originally Posted by sniper80

I was running 70g of 2217 with an Amax seated at mag length, 85mm from memory. Gave me 2950 fps and shot 0.6 moa.

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Similar here, 69.5gr 2217 and mag length 3.300", similar accuracy of better depending how I am shooting.

Quote:

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Originally Posted by Carpe Diem

Thanks @Ginga - sounds like a good place to start...

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NO, it is not yet a good place to start, I can see you are trying to go with someone load and it is NOT GOOD.
I am sorry to say it but you must follow the basic rules, "Never start a load above the maximum in the powder manufacter book", ADI recommend for 162gr amax's and similar weight "maximum of 70grains by the book", take 3% off and start from there, if you think 3% is too much start with at least 2grains bellow maximum and THEN go up, the best load in your rifle may not be the same of other rifle. Be safe or it may be your only "try" in find your good load.