New Rifle Build- Bullet and Caliber- Mono metal- Thoughts?

[Jason Snyder]

The heaviest .243 Hammer is a 104 tipped, and it shows you need a 1/7 twist.

At 18” I’d probably just start with standard powders. H4895 or H4350 are two listed. RL16 would probably be a great choice but its impossible to find.

Keep us posted. I have a Tikka 695 in a 30-06 they I’ve contemplated using for a 6CM build.

 

[pods8 (Rugged Stitching)]

3- using the suppressor above what is the lightest profile barrel I should use? I understand there is an issue with threading a suppressor onto to thin of a muzzle but don’t know the details or options out there.

Unless you want to use an adapter or flared end on the barrel the easy button is PBB or PVA both have a profile that drops down to .75” quickly and then is taperless so it has a good shoulder for 5/8-24 threads which are common. You could go smaller and save a few ounces but you’ll have to use an adapter or flare the contour at the end. Fluting might save you those same ounces if you’re chasing them.

Keep us posted. I have a Tikka 695 in a 30-06 they I’ve contemplated using for a 6CM build.

Imho get a T3/T3x for the 6cm build. The M695 is a bit heavier and you’d be wasting the 3.49” (iirc) mag length on the 6cm. Build a 6-06 on it or something that makes use of the extra length.

 

[DagOtto]

Reading this whole thread, I was thinking 6 creedmoor for sure. It meets you're requirements and you can get some damn good velocity if you step on it. Get it throated with your preferred bullet at the neck/shoulder junction and fill it full of n555.

I don't have a bunch of experience with monos because I don't use them. However sending some lighterweight monos out of my 6 creed has crossed my mind just to see what they do. I might do that next year. I have the 108eldm, 108 Berger elite hunter, and a 95gr BT to get data on this year.

You can get factory ammo, brass is super easy to come by, and it just makes the most sense to me.

Thanks for your thoughts and for the load info. This is going to be the gun build that makes me reload.. So I'm a newb when it comes to load development.

 

[DagOtto]

The heaviest .243 Hammer is a 104 tipped, and it shows you need a 1/7 twist.

At 18” I’d probably just start with standard powders. H4895 or H4350 are two listed. RL16 would probably be a great choice but its impossible to find.

Keep us posted. I have a Tikka 695 in a 30-06 they I’ve contemplated using for a 6CM build.

Thanks, I mistook that Hammer made a slightly heavier bullet. Wondering if the 1/7 twist instead of the 1/7.5 hurts performance with a lighter (95 gr.) bullet?

 

[DagOtto]

Unless you want to use an adapter or flared end on the barrel the easy button is PBB or PVA both have a profile that drops down to .75” quickly and then is taperless so it has a good shoulder for 5/8-24 threads which are common. You could go smaller and save a few ounces but you’ll have to use an adapter or flare the contour at the end. Fluting might save you those same ounces if you’re chasing them.

Imho get a T3/T3x for the 6cm build. The M695 is a bit heavier and you’d be wasting the 3.49” (iirc) mag length on the 6cm. Build a 6-06 on it or something that makes use of the extra length.

Great info on the barrel, I will lean this way for sure. And probably won't bother with fluting.. I am coming up with a rough initial weigh of 8.5 pounds (with scope and suppressor) which I do want to get down a bit. I'd go carbon as my other 2 builds have been proof carbon, but I want to use this gun as my 500+ round a year practice gun so hope to burn out barrels! Also kind of want to keep this towards the "budget" side since the action is a tikka and not Defiance etc.

I hear you on "wasting" the extra length of the action, and was leaning towards the 6-06 and others for that reason. But after reading input on this site and looking at ballistics comparison it doesn't seem to make sense. I guess you might get an extra cartridge in the magazine between 6-06 and 6cm but still......

That brings up another newbie question though: I've heard that Tikka magazines are generic and they use a spacer or filler in the back of the magazines to make them fit different cartridges. Is this true? And if so, where can I purchase fillers to change my mgs from 30-06 to 6 CM?

Appreciate all the help!

 

[pods8 (Rugged Stitching)]

That brings up another newbie question though: I've heard that Tikka magazines are generic and they use a spacer or filler in the back of the magazines to make them fit different cartridges. Is this true? And if so, where can I purchase fillers to change my mgs from 30-06 to 6 CM?

Appreciate all the help!

they are molded in, you just get the size you need. Off memory there are M (2.8something”) and M+ (2.9something”) which both use the short bolt stop. And L (3.3something”) which uses the long.

There also ones for 223 and WSM.

 

[180ls1]

Thanks, I mistook that Hammer made a slightly heavier bullet. Wondering if the 1/7 twist instead of the 1/7.5 hurts performance with a lighter (95 gr.) bullet?

For what its worth, Hammer load at 3400fps has dropped more animals (5 of 6) than any other load I have used.

I would be a speed freak with them even if you give up BC. Yes, go with the faster twist too.

 

[SDHNTR]

I just killed a bull 3 days ago with a .300 wsm and a 180 Hammer Hunter. Bull went 25 yards and crashed. Insides were obliterated. Once the hide and onside ft shoulder came off, there was a hole in the chest you could easily stick your fist in. A 6x8” chunk of destroyed lung fell out the hole with gallons of blood. Yeah, copper sucks. Let’s keep talking about it.

 

[warrbuk]

For reference Barnes factory ammo 6.5 Creedmoor 127 LRX @ 245 yards.

Not the bullet I would choose
Think about the
Hammers or Mcguire ballistics

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[SDHNTR]

For reference Barnes factory ammo 6.5 Creedmoor 127 LRX @ 245 yards.

Not the bullet I would choose
Think about the
Hammers or Mcguire ballistics

Sent from my iPhone using Tapatalk

What twist?

 

[warrbuk]

What twist?

8 twist and it happened last year on a 180# hog also.

This was on a blacktail buck.


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[SDHNTR]

Tumbling bullet, did not impact squarely. any chance at pre impact deflection off something?

 

[warrbuk]

I didnt hit anything, and I doubt tumbling as they shoot well out to 500 yards We hunt at less than 700' above sea level and it was 80-85 degrees . That bullet doesn't perform well under our conditions. It might work fine at 4500" and 60 degree temps tho.

 

[SDHNTR]

I didnt hit anything, and I doubt tumbling as they shoot well out to 500 yards We hunt at less than 700' above sea level and it was 80-85 degrees . That bullet doesn't perform well under our conditions. It might work fine at 4500" and 60 degree temps tho.

Nope. Your atmospheric examples are irrelevant as to how it may change terminal performance.That bullet absolutely tumbled for one reason or another. I shoot tons of stuff with LRX under similar conditions. They work great with enough speed, and when they are not tumbling.

 

[warrbuk]

The 124 HH pounds stuff out of the same rifle. The BC is a bit inflated tho


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[pods8 (Rugged Stitching)]

For reference Barnes factory ammo 6.5 Creedmoor 127 LRX @ 245 yards.

Not the bullet I would choose
Think about the
Hammers or Mcguire ballistics

Sent from my iPhone using Tapatalk

What impact velocity for reference?

 

[cubdriver84d]

Okay- follow up questions as I plan this build.

Quick review — I’ve got an old tikka t3 30-06 that I intend to rebuild. Goals are light backpacking build, 600 yard max range, mono metal. It will be used with a suppressor. Likely my 5.5” 7.8 oz banish backcountry.

Per the input from you all I’m now planning on building this in 6 Creedmore and shooting 95 grain DRTs or 115 grain Hammers or possibly Controller Chaos if the gun hates the DRTs.

So- folllow up questions— Id like to
Use a steel barrel cause this will also be my practice rifle for the foreseable future.

1-What twist do ya’ll think I should go with? the standard 7.5 ?

2-any concerns with 18” barrel? Do I need to
Plan on using faster burning powders with that barrel or is it a non issue?

3- using the suppressor above what is the lightest profile barrel I should use? I understand there is an issue with threading a suppressor onto to thin of a muzzle but don’t know the details or options out there.

4- I see a company called x-caliber making stainless tikka pre-fits. Anybody have experience with them?

Thanks!

Thanks, I mistook that Hammer made a slightly heavier bullet. Wondering if the 1/7 twist instead of the 1/7.5 hurts performance with a lighter (95 gr.) bullet?

I'm shooting the 95 DRT out of an 18" preferred 7 twist 0.75 straight taper with tbac ultra 7. It will rarely do better than 2" ten round groups (easily does better with factory eld). I'm sort of wondering if the 7 twist is too fast for the DRTs.

 

[DagOtto]

I'm shooting the 95 DRT out of an 18" preferred 7 twist 0.75 straight taper with tbac ultra 7. It will rarely do better than 2" ten round groups (easily does better with factory eld). I'm sort of wondering if the 7 twist is too fast for the DRTs.

Interesting, and a bit of a bummer on the accuracy side. I do wonder if that 1:7 is too fast. I'd be interested for you to try a heavier bullet and see the results. Hammer makes both a 100 and a 104 grain bullet and it would be interesting to run the 95 grain Barnes LRX through the same system to see if it's twist or just the bullet design.

I was going to order my barrel in 1:7.5 or even 1:8 since long range is not my goal or interest. But I do want to get solid 1.5" or smaller 10 round groups if I possibly can. (call me greedy?) Wondering if anyone has achieved this level of accuracy with this combo of 6 CM, 18" barrel and 95 gr. DRTS?

I found with my 6.5 CM build from earlier this year that DRT's were accurate but a far second to Lehigh Defense controlled chaos bullets. DRT's averaged 1.75 for 10 round groups where LDCC have been lights out, sub 1.5" 10 round groups.....Here is group from last week which is one of the best 100 yard groups I've shot. It's just 8 rounds. I was re-zeroing the gun because I bought new ammo from a new lot.

Wondering at what point you go with the larger group sizes to get the frangible bullet performance versus going for the smaller wound channels but which is more accurate?

I am seeing why so many have found the lead ELDM/(X) to be the easy button as they seem to be reliably delivering both accuracy and wound channel size.

 

[ropeup79]

Looks like you made a decision but the good ol 6.5x55 Swede or the AI version might fit the bill. In between the 6.5 CM and 6.5-06 with pretty readily available components.

 

[DagOtto]

Looks like you made a decision but the good ol 6.5x55 Swede or the AI version might fit the bill. In between the 6.5 CM and 6.5-06 with pretty readily available components.

Ah, I sound like I've made my mind up,, but I'm easily influenced!

I've attached my spreadsheet analysis of various cartridges. The 6.5x55 Swede seems a bit on the slow side but I do really like the idea of the 6.5-06, 6.5-284 and the .25-06 Rem.

These three would allow me to use the long action I have already and not swap out magazines. They have great velocity numbers that fit my goals and recoil is very managable. Especially once suppressed and weight is likely to be more like 8.5-9 instead of 8 which this analysis is based on. Sadly the .25-06 is out because DRT doesn't make bullets in that caliber.

So the decision really comes down to if I truly want to embrace and try-out the Rokslide / Form path of "low-recoil makes shooters not suck." If so, it seems that the 6mm CM is the obvious choice.

In terms of determining which cartridges have the longest lasting barrel life, John Barsness has a formula he proposes in his book "Obsessions of a Rifle Looney." (As an aside, I'd highly recommend all of his books to anyone who likes this stuff enough to have read this post!)

His formula is Caliber's Cross Sectional Area divided by Case Capacity.

He says,

"Cartridges with a bore/case ratio of under 10 tend to be rough on barrels, and kick noticeably harder. .....Get down around 8 and they really start to eat barrels, and buck like rodeo bulls. A bore/case ratio much above 10 results in cartridges noted for high efficiency, particularly long bore life and relatively light recoil for their ballistic results."

For ease of calculation here is the cross sectional area of various standard calibers:
6 mm/ .243- .0464
6.5 mm/ .260- .0547
270- .0602
7mm/.280- .0633
.308- .0745

I've added this column to my spreadsheet. The comparision from a barrel life basis for the cartridges being considered goes as follows: 6.5-06 (shortest barrel life), then 6.5-284, then 6 CM, then 260 REM.

Because I'm enjoying this pretty useless exercise, I want to find a reliable way to calculate and populate the last column of this spreadsheet before making a final decision. That is barrel life and inherent accuracy. Still working on how to populate these with good data so help a guy out!