95 SMK in 223, anyone try yet?

[Fuzzy1968]

Im curious to know if anyone has got their hands on the Sierra 95 SMK and have shot in their 223 yet.
I received 500 the other day and this morning started doing measurements and as I suspected, they are way too long for my chamber cut with a .169 freebore. Since I have two great shooting 6.5 twist barrels, I decided to sacrifice one barrel to experiment and cut the throat another .110 deeper with a PTG throater so the bullets sit in the neck where they are supposed to. These new 95's are pretty long, it might be a waste of a barrel or at least cost me a set back but they are worth the effort.

 

[Mark W]

Personally I would prefer a little more case capacity than a .223 has to offer for a 95 grain bullet. What kind of velocities are you expecting from this combo?

 

[556Griff]

How long are they?

 

[Ned Ludd]

http://forum.accurateshooter.com/threads/new-224-matchking.3941880/

In my hands, they're shooting extremely well so far. However, you're really going to want a 32" barrel and a throat with somewhere in the neighborhood of .250" to .300" freebore, possibly even a little more, in order to get the most out of them. A rifle throated for 90 VLDs with a 30" barrel will run into major pressure issues with the 95s when trying to hit the node analogous to that of running the 90s in the 2820-2850 fps range with Varget or H4895. If you drop the velocity sufficiently to alleviate the pressures issues with the small .223 case, you'll largely be giving up the ballistic advantage of the 95 SMK.

 

[B23]

How long are they?

Mine are 1.293 long but I read through that other thread and one guy said his were considerably shorter while another guys were a tick longer at 1.300. All I know is I measured five of them and they all were nearly exactly the same, give or take a thou, at 1.293.

 

[watercam]

http://forum.accurateshooter.com/threads/new-224-matchking.3941880/

In my hands, they're shooting extremely well so far. However, you're really going to want a 32" barrel and a throat with somewhere in the neighborhood of .250" to .300" freebore, possibly even a little more, in order to get the most out of them. A rifle throated for 90 VLDs with a 30" barrel will run into major pressure issues with the 95s when trying to hit the node analogous to that of running the 90s in the 2820-2850 fps range with Varget or H4895. If you drop the velocity sufficiently to alleviate the pressures issues with the small .223 case, you'll largely be giving up the ballistic advantage of the 95 SMK.

I noticed that Sierra used some slower powders in their load data (but kept the OAL appropriate for a standard chamber - in other words, useless). Couple of 4350 burn rate powders in there. Might be worth a try if I can bring myself to cut an even longer throat. Also wondering about barrel life!

 

[paperpuncher]

http://forum.accurateshooter.com/threads/new-224-matchking.3941880/

In my hands, they're shooting extremely well so far. However, you're really going to want a 32" barrel and a throat with somewhere in the neighborhood of .250" to .300" freebore, possibly even a little more, in order to get the most out of them. A rifle throated for 90 VLDs with a 30" barrel will run into major pressure issues with the 95s when trying to hit the node analogous to that of running the 90s in the 2820-2850 fps range with Varget or H4895. If you drop the velocity sufficiently to alleviate the pressures issues with the small .223 case, you'll largely be giving up the ballistic advantage of the 95 SMK.

In your experience how much twist is actually required for this bullet. Planning a 223 rem at around 1000' above sea level. Going to order a tube and try these out this spring. What contour do you prefer for a 32" tube. Can I simply chamber with the issf reamer and just move the throat out to .250-.300".

 

[Ned Ludd]

Minimum 6.8 twist necessary for full BC at 65 degrees and 500 ft elevation, according to Berger's Twist Rate Calculator. Slightly faster if you're shooting on the beach in January and February, maybe a 6.5-twist.

Yes, a barrel cut with the ISSF reamer and then throated longer should definitely work. As far as contours for a 32" barrel, I'd go with whatever the heaviest contour is that allows you to safely make weight with the rest of your specific setup.

 

[paperpuncher]

Minimum 6.8 twist necessary for full BC at 65 degrees and 500 ft elevation, according to Berger's Twist Rate Calculator. Slightly faster if you're shooting on the beach in January and February, maybe a 6.5-twist.

Yes, a barrel cut with the ISSF reamer and then throated longer should definitely work. As far as contours for a 32" barrel, I'd go with whatever the heaviest contour is that allows you to safely make weight with the rest of your specific setup.

Thanks for the advice I sent you a pm

 

[Alfred]

Thanks for the advice I sent you a pm

How did it finally workout with the 95gn Sierra

 

[paperpuncher]

I was happy with them. I shot a 32" 6.75" twist barrel. I used the ISSF reamer and then I extended the throat another .051. I shot them at 2750 fps with .015-.020 jump. My scores improved as the year went on I had to get comfortable with the combo

 

[Boisblancboy]

I was happy with them. I shot a 32" 6.75" twist barrel. I used the ISSF reamer and then I extended the throat another .051. I shot them at 2750 fps with .015-.020 jump. My scores improved as the year went on I had to get comfortable with the combo

How’s your brass life?

 

[Ned Ludd]

How did it finally workout with the 95gn Sierra

I finally got out with the 95s a while back and set the tuner at 100 yd before heading over to the 600 yd range. It was almost dark and I could barely see the orange aiming dot on the 18" Shoot-N-C target, let alone bullet holes. Nonetheless, I was able to break a couple orange shotgun clays someone had left on the back berm near my target (~620 yd), so I figured it had to be on paper. I held center as best I could and sent the last 10 shots downrange. I was very surprised (and pleased) when I drove down to pick up the target. Rings inscribed in the target are the standard 3", 6" and 12" diameters for F-Class X-, 10-, and 9-rings. I think the 95s are showing some promise .

 

[paperpuncher]

How’s your brass life?

I did some research before jumping in on this. There is a wealth of info on this forum and some very smart individuals from whos experience I have benefited. In my conversations it was pointed out that brass life would benefit from a moderate first loading to 'fireform" the brass. My current brass is has been fired 4X including the fireform I have not lost any cases yet. I suspect that things will start to change on the next loading but we will see. Consensus is about 4 loadings and you will start to have cases falling out

 

[jsthntn247]

I finally got out with the 95s a while back and set the tuner at 100 yd before heading over to the 600 yd range. It was almost dark and I could barely see the orange aiming dot on the 18" Shoot-N-C target, let alone bullet holes. Nonetheless, I was able to break a couple orange shotgun clays someone had left on the back berm near my target (~620 yd), so I figured it had to be on paper. I held center as best I could and sent the last 10 shots downrange. I was very surprised (and pleased) when I drove down to pick up the target. Rings inscribed in the target are the standard 3", 6" and 12" diameters for F-Class X-, 10-, and 9-rings. I think the 95s are showing some promise .

View attachment 1083577

What's the BC looking like on those?

 

[Ned Ludd]

I have determined the average G7 BC of the 95 SMKs and pointed 90 VLDs on a number of different occasions using LabRadar velocity data and JBM Ballistics. The results for both always seem to range from about 0.290 to 0.293.

 

[K22]

I'm not being flippant but educate me - why would you want to shoot bullets this heavy out of a small case like a 223 Rem?

Wouldn't the trajectory be like a rainbow?

 

[Jdne5b]

Trajectory is only a part of what some people are after. For Fclass known distance shooting.. I only care about wind drift and raw accuracy. Im sure drop figures into it somewhere but it really doesnt matter weather I come up 27mins or 29mins.. if coming up 29 mins gets me less wind drift for same or better accuracy then Im happy.

 

[Ned Ludd]

I'm not being flippant but educate me - why would you want to shoot bullets this heavy out of a small case like a 223 Rem?

Wouldn't the trajectory be like a rainbow?

The uber-heavy .223 Rem bullets (88s, 90s, 95s) don't give up a huge amount in terms of wind resistance, but they can be loaded and fired with outstanding precision In F-TR competition due to the almost complete lack of recoil relative to a .308 Win pushing 200 gr bullets. This is especially true in midrange comps (out to 600 yd). The downside is generally poor brass life.

 

[Boisblancboy]

The uber-heavy .223 Rem bullets (88s, 90s, 95s) don't give up a huge amount in terms of wind resistance, but they can be loaded and fired with outstanding precision In F-TR competition due to the almost complete lack of recoil relative to a .308 Win pushing 200 gr bullets. This is especially true in midrange comps (out to 600 yd). The downside is generally poor brass life.

@Ned Ludd couple questions for you. What speeds are required to get optimal BC for the 90’s vs an 80?

Also at those optimal speeds for an 80 is brass life much better vs the 90’s?