Sako A7 6.5 Creedmoor

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Sako A7 6.5 Creedmoor

Post by Flyer » 05 Feb 2020, 8:43 pm

Talking about Tikkas, Howas and 6.5 Manbuns lately made me think of my Sako A7 Roughtech Pro. So I decided to try some new loads out the other day. I didn't get very far.

Some might wonder why you would buy an A7 when you could buy a cheaper Tikka or a "better" Sako 85. One thing the A7 Roughtech rifles have that the Tikkas and Sako 75s/85s don't is an aluminium chassis – a better bedding system than either the Tikka T3x or Sakos, IMO, and reason enough to consider them.

At the time of purchase, there was no 6.5CM in Tikka or Sako 85 – they came out later – so the A7 Roughtech Pro and Range were my only choices in those rifles.

Out on the range, first shot was a fouler. The next five shots went into .350" at 100M and all six (including fouler) went into .625", including three through one hole. That was the start and end of my load development. 8-)
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143gr ELD-X, 41.8gr of 2209, Lapua small-primer brass, BR4 primers, 2.850" OAL (0.084" off the lands), chronoed at 2700fps

Apart from the 143gr ELD-X, I have a softer target load: 123gr Lapua Scenar; 43.2gr 2209, Lapua small-primer brass, BR4 primers, 2.850" OAL (0.015" off the lands), chronoed at 2835fps.

4x shots at 100m
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123gr Lapua Scenar vs 143gr Hornady ELD-X, both in Lappy SRP brass
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Rig
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Incidentally, that 41.8gr load is very similar to some of these loads: viewtopic.php?f=3&t=8627&start=18

I think JimTom's ELD-X load is similar (41.5gr 2209 from memory) in the same rifle.

These rifles can be bought for under $2k and sometimes as low as $1500 in excellent second-hand condition. They shoot straight out of the box. I reckon the 6.5 Creedmoor round also helps.
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Re: Sako A7 6.5 Creedmoor

Post by JimTom » 05 Feb 2020, 9:08 pm

Great results mate.
You have a great memory mate. Yep my load for the 143 ELD X is 41.5gr AR2209 and a 2.85” OAL the same as yours mate.
I agree, the Sako A7 is a great rifle. I’d buy another in a heartbeat.
Here is my target, 5 shots at 100m. I also had a flyer at the end, it was me not the rifle otherwise it would have been a cracking group.
Still I am Happy with 0.6” at 100m. Group would have been half that if I was competent. :drinks:
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Re: Sako A7 6.5 Creedmoor

Post by Bill » 05 Feb 2020, 9:10 pm

gotta be happy with those groups Flyer :drinks:
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Re: Sako A7 6.5 Creedmoor

Post by AZZA'S HJ47 » 05 Feb 2020, 9:40 pm

Love my sako A7 accurate and light enough to carry around. As you said the only thing i dont like is that i cant top feed it like my 85.
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Re: Sako A7 6.5 Creedmoor

Post by Flyer » 05 Feb 2020, 9:55 pm

AZZA'S HJ47 wrote:Love my sako A7 accurate and light enough to carry around. As you said the only thing i dont like is that i cant top feed it like my 85.

Are you sure mate? The A7s are designed to be top-loaded, which is why they have that "hybrid" plastic magazine with metal feed lips.

You're right about it being light enough to carry around. I like Howas, but the actions are heavy. I wasn't sure at first whether to get the Sako A7 Roughtech Pro or Range model (the only Sakos in 6.5CM at the time), but I settled on the Pro because it "felt" right for shooting offhand. With a 24.4" medium contour fluted barrel, it is nicely balanced and tops the scales at 3.4kg.

The forestock is thinner than the Range model, too, which is really set up for bench or bipod shooting. It has a 26" medium-heavy barrel, and you can feel the extra weight – 4.2kg – when holding it offhand.

My concern was the lighter barrel would go off the boil after a few shots when it warms up, but it doesn't. Those six shots were in pretty quick succession. The barrel does heat up, but cools down pretty quick, too. It's a great off-hand rifle. For prone work, I'd probably go the Roughtech Range.

I should add that the single trigger is very nice, too. Better than the single trigger on my Sako 85 (which I swapped for a set trigger).
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Re: Sako A7 6.5 Creedmoor

Post by Stix » 05 Feb 2020, 10:06 pm

Some nice groups there guys... :mrgreen:

Got me all excited & thinking i should get one of those instead of a Tikka in a 6 or 6.5 for hunting...but to read cant be top fed--why would you buy it over a Tikka for a hunting rig if you cant top feed it... :unknown:

Worth checking Azza...& report back eh...?... :thumbsup:

And a pleasant surprise Flyer... :)
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Re: Sako A7 6.5 Creedmoor

Post by Flyer » 05 Feb 2020, 10:06 pm

JimTom wrote:Great results mate.
You have a great memory mate. Yep my load for the 143 ELD X is 41.5gr AR2209 and a 2.85” OAL the same as yours mate.
I agree, the Sako A7 is a great rifle. I’d buy another in a heartbeat.
Here is my target, 5 shots at 100m. I also had a flyer at the end, it was me not the rifle otherwise it would have been a cracking group.
Still I am Happy with 0.6” at 100m. Group would have been half that if I was competent. :drinks:

Great group, mate! 41.5-41.9gr of 2209 seems to be the sweet spot for this cartridge in the 140 grainers. I shot an OK group with 42.5gr of 2209, but it was in-between nodes, as the horizontal string was good, but the vertical string showed a bit of variation. I shot 42.8gr as well, but that was starting to show pressure signs (flatter primers, slight ejector marks).

Bill wrote:gotta be happy with those groups Flyer :drinks:

Yes mate. For a medium-priced rifle – in fact cheaper than some of the tactical Tikkas – I think it's good value and well-designed. Sako/Tikka barrels and actions have always been good, but I've never much liked their bedding systems. The A7 Roughtech models have among the best synthetic stocks on the market and the alloy chassis system is what makes them so consistent, IMO.

I just laugh when people make fun of the 6.5 Creedmoor :lol:
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Re: Sako A7 6.5 Creedmoor

Post by Flyer » 05 Feb 2020, 10:13 pm

Stix wrote:Some nice groups there guys... :mrgreen:

Got me all excited & thinking i should get one of those instead of a Tikka in a 6 or 6.5 for hunting...but to read cant be top fed--why would you buy it over a Tikka for a hunting rig if you cant top feed it... :unknown:

Worth checking Azza...& report back eh...?... :thumbsup:

And a pleasant surprise Flyer... :)

Top feed was one of the main considerations when I got it – mine definitely top loads.

There have been some complaints about the A7 magazines – specifically the metal feed lips losing tension – but I think that in at least some of the cases it's because people are over-feeding them.

The A7 magazine is a bit strange, because it is ostensibly a 3-shot mag – but you can fit 4 rounds in there. If you do put 4 rounds in the mag, then the top round can sometimes pop out – either inside the rifle (won't load), or outside.

The problem isn't the magazine, it's that owners forget how many rounds they're supposed to load. I was guilty of that myself – and thought the mags were a bit dodgy – until I realised it was user error, and not the fault of the magazine.

This was supposed to be my metallic silhouette rifle, as the .243 Bavarian wasn't cutting it on the rams, but then I moved away from the club and haven't shot the 6.5 much since. I have shot it in Field Rifle matches, but it kicks more than my .223 (but not much more than the .243) so is harder to shoot offhand. It's also more expensive. But thanks to JimTom, I managed to pick up 500x 143gr ELD-X projectiles for a great price last year.
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Re: Sako A7 6.5 Creedmoor

Post by AZZA'S HJ47 » 05 Feb 2020, 10:59 pm

I'll have to have another look i think i may have accidentally pushed on into the mag. Hope to use it for chasing deer out to 500m. No ptoblems out to 300 have to try a diffrent range to stretch the legs out and get some practice in.
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Re: Sako A7 6.5 Creedmoor

Post by JimTom » 06 Feb 2020, 8:02 am

G’day Azza

Mate those magazines in the A7 can be top fed without removal from the rifle.
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Re: Sako A7 6.5 Creedmoor

Post by bigrich » 06 Feb 2020, 9:16 am

I had a A7 in 308, great trigger, light, and silly accurate. If they made one in 223 I would’ve bought it instead of the Sauer 100 I got coming. You can top load and they are a step up from a Tikka in my opinion :thumbsup:
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Re: Sako A7 6.5 Creedmoor

Post by SCJ429 » 06 Feb 2020, 5:54 pm

Flyer wrote:Talking about Tikkas, Howas and 6.5 Manbuns lately made me think of my Sako A7 Roughtech Pro. So I decided to try some new loads out the other day. I didn't get very far.

143gr ELD-X, 41.8gr of 2209, Lapua small-primer brass, BR4 primers, 2.850" OAL (0.084" off the lands), chronoed at 2700fps

Apart from the 143gr ELD-X, I have a softer target load: 123gr Lapua Scenar; 43.2gr 2209, Lapua small-primer brass, BR4 primers, 2.850" OAL (0.015" off the lands), chronoed at 2835fps
.

I am suprised that the mighty Creedmoor shoots 143 grain ELDX at 2700 fps. I use a 143 grain ELDX in my humble 260 Rem at it shoot them at an average speed of 2901 fps using 44.5 grains of 2209. Tons of extra space to push it further and no pressure signs.
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Re: Sako A7 6.5 Creedmoor

Post by Flyer » 06 Feb 2020, 7:39 pm

Well I guess an extra 3gr of 2209 may account for much of the extra velocity. At 42.8gr I had a full load (not quite compressed) and the pressure signs were just starting; ie, the primers were starting to flatten and there were very light ejector marks on the rim. But that load was nowhere near as accurate as 41.8gr.

Perhaps the only caveat is when we chronoed 41.5g (2670fps) and 42.5g (2730fps) of 2209, the barrel was very new and only just run-in (about 50 rounds), so it might be slightly faster now. But that's just a guess and I won't know until I borrow the chrono again.

The highest 2209 load I've seen in a 6.5CM with the 143 ELD-X is 43.4gr in this video: https://www.youtube.com/watch?v=r0gQCmnYmHU

He got 2780fps from that load in a 22" barrel. The interesting thing about the video is he used Starline small rifle primer brass, which is almost identical to Lapua SRP brass (internal volume, overall weight). So his loads would be close to mine. His seating depth is .050" shallower (2.800" OAL vs my 2.850").

Make what you will of that, but his velocity figures were not far removed from mine. Maybe mine should be a little quicker with the 24.4" barrel, but as stated, mine was a brand new barrel at the time.

The above figures are also very similar to Hornady's own figures here - 2700fps with 41.5gr of 2209 (H4350) in a 24" barrel:

Image

OK, I've just found some more chronoed load data and there is a post in this lot of someone cramming 45gr of 2209 into a 6.5CM in a Tic-Tak and getting 2820fps: https://www.nzhuntingandshooting.co.nz/ ... ads-39670/

That's a lot of extra powder for an extra 100fps, and still behind your 260. You obviously have a fast barrel.
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Re: Sako A7 6.5 Creedmoor

Post by SCJ429 » 06 Feb 2020, 8:15 pm

Thanks for the info, I always thought the Creedmoor had about 150 fps advantage over a 260 using small primer Lapua brass. I use large rifle primers but a 28 inch Maddco barrel with a tight chamber and have to neck turn.

I rate the Creedmoor case, it looks like a very nice thing. I thought about putting a 40 degree shoulder on the 260 so I could look a bit cooler when someone with a Creedmoor turns up. Keep posting your results with your Sako, great stuff.
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Re: Sako A7 6.5 Creedmoor

Post by Bill » 06 Feb 2020, 9:59 pm

SCJ429 why would you think a 6.5 CM would have a 150 fps advantage over the 260 ?

I chrono'd my 22 inch 260, 140gr top load was 2865 fps with 46gr of 2209. 45gr gave 2815 fps.
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Re: Sako A7 6.5 Creedmoor

Post by SCJ429 » 07 Feb 2020, 6:29 am

Because of the higher pressures you can generate using small primer brass and the more efficient case design. It is also interesting that a six inch shorter barrel, and a standard barrel I assume you are using is only costing you less than 100 fps. Thanks for the info Bill.
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Re: Sako A7 6.5 Creedmoor

Post by Bill » 07 Feb 2020, 6:51 am

ho much pressure diff with small primers ?? efficiency is an interest term, I dont see much of a diff between the CM and 260 to be honest and more capacity allows lower pressure and longer brass life. Ive run 140gr over 2900 but cause it got use in 40 deg plus weather I backed off a grain. This was in a short action too :thumbsup:
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Re: Sako A7 6.5 Creedmoor

Post by sungazer » 07 Feb 2020, 2:52 pm

I have a Howa 24 inch 6.5 C and a load I have used is 42.3grn of 2209 which gave 2750 fps at 2.835 COAL which would be about 80 thou off the lands.
The small rifle primers dont affect the overall pressure but because of the smaller flash hole the pressure back on the primer is less.

For Alpha brass that has a flash hole of 2mm larger than even a normal Large Rifle primer I would be concerned about pressure on the primer. I drilled out a few SR pockets to LR flash hole specs and found the SD to increase. Even more than I was experiencing with the worn flash holes in the SR brass.
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Re: Sako A7 6.5 Creedmoor

Post by Flyer » 07 Feb 2020, 6:12 pm

^ That's pretty much inline with my chrono: 2730fps from 42.5g of 2209.

The small rifle primers also increase the structural strength of the primer pockets compared to larger primers, as there's obviously more brass in that area. They are less likely to become loose over time under higher pressure loads, so you can get more reloads out of them.

These guys fired and reloaded a Lapua 6.5CM case 22 times without issue: https://www.65guys.com/a-look-at-lapua- ... oor-brass/

Their load was a 140gr ELD with 43.1gr of 2209 with an average velocity of 2871fps over the 22 shots. They reckon that's a "hot" load. The Lappy SRP brass handled it with aplomb.
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Re: Sako A7 6.5 Creedmoor

Post by Flyer » 07 Feb 2020, 6:28 pm

What sold me on the 6.5 Creedmoor was that a 7-08 typically starts off with 250ftlb more energy and a 308 starts off with 350ftlb more, but by the time they all reach 500m, they're all carrying similar energy to knock down rams (metallic silhouette). The 6.5 is usually within 50 ft lbs of both, and it's already much easier to find ammo, projectiles and brass for than 7-08.
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Re: Sako A7 6.5 Creedmoor

Post by Bill » 08 Feb 2020, 9:42 am

I think the SR primer V LR primer is probably only the domain of the mad scientist long range shooter tinkerer, choice of powders and weather conditions would indicate its not going to deliver for average joe.... :thumbsup:

Dave Emary, Hornady's chief ballistician and originator of the 6.5 Creedmoor had this to say about the issue ' Typical 6.5 Creedmoor powder charges are simply too large to reliably ignite with Small Rifle primers under all conditions. They're just fine for .223 and similar capacity rounds; however, we're talking about nearly twice as much propellant. A Large Rifle primer is definitely needed to assure reliable and consistent ignition. If the throat is eroded and a round hang-fires, the bullet will plug the bore, and the reigniting propellant will likely fully burn before the bullet can began moving again. Skyrocketing pressures may damage the rifle and possibly injure the shooter.'
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Re: Sako A7 6.5 Creedmoor

Post by JimTom » 08 Feb 2020, 9:46 am

I use CCI 450 small rifle magnum primers in my 6.5CM. Whilst I would never argue the case with Hornadys chief ballistician, I have never had any issue of unburned powder etc. Seems to be working ok for me so far.
I can’t see how this is any different to those blokes who use the .308 Palma brass with SRP. They don’t seem to have a problem.
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Re: Sako A7 6.5 Creedmoor

Post by Bill » 08 Feb 2020, 9:49 am

you live in QLD JimTom so cold temps and ignition isnt going to be an issue and im guessing you use ADI powders and not Alliant reloader ??
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Re: Sako A7 6.5 Creedmoor

Post by JimTom » 08 Feb 2020, 9:55 am

Yeah that is true mate, I am in NQ so pretty much hot all year round. I am loading AR2209 mate.
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Re: Sako A7 6.5 Creedmoor

Post by sungazer » 08 Feb 2020, 12:26 pm

Bill that is absolute crap. Every 308 target shooter uses Lapua SR primers because they deliver a much more consistent ignition and hence a small ES which is needed when shooting long distance. The 6.5 being the same case as the 308 but a little smaller and typically using about 2 grains less powder benefits in the same way as the 308.
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Re: Sako A7 6.5 Creedmoor

Post by SCJ429 » 08 Feb 2020, 1:56 pm

They are talking about shooting in subzero temperatures. If Hornady made factory ammo and someone tries shooting it at minus 30, they want it to ignite reliably. I have used Palmer brass for my 243 and never had an issue with BR4 or 450 magnum primers. I never shoot in extremely cold conditions.
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Re: Sako A7 6.5 Creedmoor

Post by Bill » 08 Feb 2020, 5:03 pm

sungazer wrote:Bill that is absolute crap. Every 308 target shooter uses Lapua SR primers because they deliver a much more consistent ignition and hence a small ES which is needed when shooting long distance. The 6.5 being the same case as the 308 but a little smaller and typically using about 2 grains less powder benefits in the same way as the 308.



what exactly is crap sungazer ? The bloke who designed the Creedmoor :lol: :lol:

Im just wondering whether the benefits are really there for the CM, Ive found a few tests where they found no increase in speed but maybe a minor diff in ES. Its an interesting topic no doubt. Sungazer I was questioning the apparent speed improvement, read the thread again :thumbsup:
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Re: Sako A7 6.5 Creedmoor

Post by SCJ429 » 08 Feb 2020, 5:23 pm

Bill wrote:]Bill that is absolute crap. .


what exactly is crap sungazer ? The bloke who designed the Creedmoor :lol: :lol:

Im just wondering whether the benefits are really there for the CM, Ive found a few tests where they found no increase in speed but maybe a minor diff in ES. Its an interesting topic no doubt. Sungazer I was questioning the apparent speed improvement, read the thread again :thumbsup:


You are saying that there is no advantage in using small primers over large primers. He is saying that this is wrong.

The Hornady guy is saying that a small primer will not work for the large powder charges the CM has in all conditions. The conditions that are an issue with ignition are sub zero temperatures. When did you last compete when the temperature was minus 10?

He is saying this because Hornady brass is large primer but the opposition , Lapua, offer superior brass with small primer pockets. There is no way he could have conceded that Lapua brass is better for the Creedmoor that Hornady was involved in creating.
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Re: Sako A7 6.5 Creedmoor

Post by SCJ429 » 08 Feb 2020, 5:30 pm

Bill wrote:
Im just wondering whether the benefits are really there for the CM, Ive found a few tests where they found no increase in speed but maybe a minor diff in ES. Its an interesting topic no doubt. Sungazer I was questioning the apparent speed improvement, read the thread again :thumbsup:


Is the reason that you found no improvement in speed because you did not explore the pressure limits of large primer brass over small primer brass? You may find that the larger mass of brass at the case head of small primer brass will tolerate more pressure. There is no point sticking 41 grains in each and concluding that the speed is about the same. Fill the case up until you see the shiny extractor mark on the case head. My bet is the Lapua brass is more tolerant of this pressure long after your Hornady brass has blown the primer.
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Re: Sako A7 6.5 Creedmoor

Post by Bill » 08 Feb 2020, 6:29 pm

SCJ429 I said I found a few tests not that I tested :thumbsup: I own a grendel and swede which get shot the most at the moment but I have no doubt Ill get a CM when the right rifle pops up.

And its an interesting topic for me as plenty of the Deer hunting season down here usually corresponds with the first big frost ( -2 to 0 degs) and when at 1000m plus ammo can get exposed to -5 to -8 deg overnite.

A few references have mentioned that with CM SR loads another 0.5 to 1.0 gr was required to get similar speeds to LR loads, is this the norm ? :drinks:
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