sierra 7mm 183 matchkings

[double g]

How are they shooting compared to Berger's 180 Hybrid? DG

 

[brxbrad]

You are going to have to have the right barrel to shoot the Sierra. I shoot the Berger Hybrid with a Bartlein 1:9 5R and I am very satisfied. With the cost of going to a 1:8 barrel plus smitty work, it will be a while before I'll be testing the Sierra. It I not mistaken, I believe you can get .700+ BC if you point the Berger.

From the Berger Web Site
Berger 180 gr Hybrid Target
G1 BC G7 BC G7 Form Factor Minimum Twist Rate Optimal Twist Rate
0.680 0.349 0.915 1:10″ 1:8.9″

From the Sierra Web Site
This bullet was introduced in October 2015.
This bullet requires a barrel twist rate of 1x8” or faster.
Dia. (inches) Weight (grains) Sectional Density
0.284 183 .324
Ballistic Coefficients and Velocity Ranges
0.707 @ 2300 FPS & ABOVE
0.713 BETWEEN 1720 FPS & 2300 FPS
0.690 @ 1720 FPS & BELOW

 

[M99]

Just got a box of 500 today and I'll be testing them in my 7 RSAUM soon. It has a 1:8.25 Bartlein 5R barrel, so we'll see how they do. Currently using Berger 180 Hybrid which shoot very well, but I found through recent testing that the Bergers shot slightly better groups not pointed, so I'll stop pointing those.

 

[Terry]

Started testing this week. Groups ran from 0's to .4 two shots at 100 yards.
Shot two shot groups for powder load developement.
284 Shehane with H4831.
Will test at 600 soon.
3 loads had ES of 6fps or less.
2600-2800 fps.

 

[M99]

Just did some range testing of them today. They shot better groups and better ES than the 180 Bergers do in my rifle. However, I could only push them about 80 fps slower than the 180 Bergers. The better BC makes up for about half the slower bullet, but the better groups were impressive and I found a very large node where the ES's stayed in the single digits. I'll definitely be shooting them in matches next year.

 

[kyreloader]

I sorted 480 of these bullets by base to ogive measurements using the Sinclair bullet sorting stand. I set my gauge to 2 thous for my first bullet, then proceeded to measure the rest I had left in the box. Here are how the box measured for me:

0.000" - 6
0.001" - 183
0.002" - 137
0.003" - 91
0.004" - 56
0.005" - 7

Just FYI, plan to start a load workup for these soon as I am expecting my barrel from my smith soon.

 

[dkhunt14]

Sierra tends to be on the safe side when calling for twists. The 240 SMK calls for a 9 twist but everybody I know shot them out of a 10 twist for 1000 yard BR. They shot great at 1000 yards entering the paper straight and making small holes. They were stabilized. I would not be afraid to try them in a 9 twist. Matt

 

[Sheldon N]

What's the length of the Sierra 183gr?

 

[painless2]

What's the length of the Sierra 183gr?

What freebore is needed?
Tom

 

[KenOath]

What freebore is needed?
Tom

Yes id also like to know what freebore is needed??

Cheers Rustij

 

[Rope2horns]

I shot them out of a Brux 9twist .225fb (Shehane)...from 35-90 degrees at 500ft elevation to whatever the elevation is at BSWN. I'm not saying they will work in all 9twist but they did in mine.

 

[falconpilot]

Freebore - .215 keeps the base of the bullet .020 above the donut region with the bullet seated back for a .030 jump.

Not home to check, but I believe I remember the length being 1.640.

 

[Jim Hardy]

Just got a box of 500 today and I'll be testing them in my 7 RSAUM soon. It has a 1:8.25 Bartlein 5R barrel, so we'll see how they do. Currently using Berger 180 Hybrid which shoot very well, but I found through recent testing that the Bergers shot slightly better groups not pointed, so I'll stop pointing those.

M99:

Respectfully, I have never had a 180 Hybrid that I could not point to print better groups and much better waterline at 1000 yards than the non pointed Hybrid. This might be something you want to consider before you point. 11 to 17 percent of the Hybrids have folded jackets. I just closed the meplats on 1500 180 Hybrids for a very well known prone shooter. They shoot lights out -- but there were 188 folded jackets in the lot that I had to sort out so he would not shoot them in the record strings with the no-folded jacket record bullets.

So, you cant close the meplats the same and shoot them with the unfolded jacketed bullets and expect the best. I have an advanced technique to find this on every meplat I close, but you can find the same thing by a pre-point inspection. Simply place the tip of a safety pin or a small punch pin in the meplat. If it goes in nicely, you are good to go with your pointing process. If it jams up, you have a folded jacket and need to sort them separately from the record rounds. I have had this tested by world class shooters and thousands of Hybrids from 105 to 230 grains. All of these groups have folded jackets within that group. A 1000 yard BR World Record holder has found this sorting very significant.

I hope this helps,
Jim Hardy

 

[Alexander-M]

M99:

Respectfully, I have never had a 180 Hybrid that I could not point to print better groups and much better waterline at 1000 yards than the non pointed Hybrid. This might be something you want to consider before you point. 11 to 17 percent of the Hybrids have folded jackets. I just closed the meplats on 1500 180 Hybrids for a very well known prone shooter. They shoot lights out -- but there were 188 folded jackets in the lot that I had to sort out so he would not shoot them in the record strings with the no-folded jacket record bullets.

So, you cant close the meplats the same and shoot them with the unfolded jacketed bullets and expect the best. I have an advanced technique to find this on every meplat I close, but you can find the same thing by a pre-point inspection. Simply place the tip of a safety pin or a small punch pin in the meplat. If it goes in nicely, you are good to go with your pointing process. If it jams up, you have a folded jacket and need to sort them separately from the record rounds. I have had this tested by world class shooters and thousands of Hybrids from 105 to 230 grains. All of these groups have folded jackets within that group. A 1000 yard BR World Record holder has found this sorting very significant.

I hope this helps,
Jim Hardy

Jim, this is very helpful, and I have a question -

I just sorted 100 Berger 284/7mm Hybrid 180-gr bullets using the safety pin method.

(A) The pin went in easily into 79 of the bullets
(B) Went in nicely but only after I slightly changed the angle of the pin in five of the bullets.
(C) Did not go in at all in 16 of the bullets

So you could say I ended up with three groups: (A) Clear, (B) Partially blocked?, and (C) Blocked.

Would the partially blocked bullets be unsuitable for pointing?

Thank you!
Alex