243 Win & 107 SMK with a 26" 1/9 bbl?

[TP4]

243 noob here. I am working up some loads for a new Rem 700 in .243 Win, with a 26" 1/9 twist barrel. I'm using 107gr SMK and Reloder 22. I started at 42gr and worked up to 44 gr in three grain increments.
Anybody have any experience with this projectile and barrel length/twist? I figure I'm going to have to push them close to 3000 fps to stabilize.
Any input appreciated.

 

[desertHK]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

Stock Remy barrels are not true 1:9" twist. I am shooting the 105 grains (AMAX and scenars). At the ceiling end of RL 22 for a 105 grains bullets requires about 45 grains of powder. With that, I was able to get only about 2850 fps for the 105 grains projos. So, you may have a hard time reaching 3000 fps with that.

When I switched over to Retumbo, I get better velocity. My best velocity is with N550 (3000 fps), but it's hard to find N550 these days, not to mention the cost.

Be interested to see if it would stabilize the 107 grains.

 

[TP4]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

DezHK, thanks for the input. Yeah, Rem lists the bbl as 9 1/8 twist. I have read that a lot of guys are using RL 25. I have some N170 I could try.
This is the only data I could find for RL 22.

<div class="ubbcode-block"><div class="ubbcode-header">Code:</div><div class="ubbcode-body ubbcode-pre" ><pre>
Cartridge : .243 Win.
Bullet : .243, 107, Sierra HPBT MatchK 1570
Useable Case Capaci: 47.592 grain H2O = 3.090 cm³
Cartridge O.A.L. L6: 2.710 inch = 68.83 mm
Barrel Length : 26.0 inch = 660.4 mm
Powder : Alliant Reloder-22

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.0% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill.Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-03.0 98 43.65 2955 2075 52545 10278 98.8 1.323 ! Near Maximum !
-02.0 99 44.10 2986 2118 54378 10349 99.1 1.303 ! Near Maximum !
-01.0 100 44.55 3016 2161 56273 10415 99.3 1.283 ! Near Maximum !
+00.0 101 45.00 3046 2204 58235 10476 99.5 1.264 ! Near Maximum !
+01.0 102 45.45 3076 2248 60268 10532 99.6 1.245 !DANGEROUS LOAD-DO NOT USE!
+02.0 103 45.90 3106 2292 62375 10582 99.8 1.227 !DANGEROUS LOAD-DO NOT USE!
+03.0 105 46.35 3136 2336 64559 10627 99.9 1.208 !DANGEROUS LOAD-DO NOT USE!

Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 101 45.00 3182 2405 70721 10089 100.0 1.168 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 101 45.00 2852 1932 46435 10330 94.5 1.391

_
</pre></div></div>

 

[dksd39]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

It might be worth your effort to try some Ramshot Hunter. I worked up a load for my DTA rifle and it loves it...

105gr A-Max
rem brass
federal primers
44.5gr Hunter
with this load I am getting @3025 fps with no pressure signs
cant remember but OAL off the top of my head but these flat out shoot.

 

[TP4]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

DezHk, I finally got the Rem 700, 26" 1/9 twist bbl to the range today. No problems stabilizing the SMK 107 gr projectiles. With RL 22 and a COAL of 2.710 I started at 42.5 grains and worked up to 44 gr. No keyholing, even at 42.5 gr. I had several one hole groups at 100 yards. It seemed to like the 43.5 gr charge. I will post some chrono numbers after Sundays session.

 

[desertHK]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

Would be interested in the velocity on those 107 SMK. I would guess somewhere around 2650's.

 

[TP4]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

DezHK,
Here are the crono averages for the RL 22 & 107 SMK. 26"bbl 1/9 twist.
43.5 gr 2,903 fps
43.8 gr 2,922
44.0 gr 2,965
44.2 gr 2,993
44.5 gr 3,006

 

[desertHK]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

That's freaking impressive. Are you using the same OAL for the 105 grains when loading these 107 SMK?

 

[desertHK]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: hammerdown</div><div class="ubbcode-body">DezHK,
Here are the crono averages for the RL 22 & 107 SMK. 26"bbl 1/9 twist.
43.5 gr 2,903 fps
43.8 gr 2,922
44.0 gr 2,965
44.2 gr 2,993
44.5 gr 3,006 </div></div>

What kind of groupings are you getting with these velocities? One of my reloading data showed that the upper limit for RL22 is 43.5 grains. You are one grain over the max. Any pressure sign? ALso, what type of primers are you using?

 

[TP4]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

DezHk,
I have not been able to try the 105 A-Max yet. I was using a OAL of 2.710 with the 107 SMK and Winchester primers. I have not yet begun to play with seating depth. At 44.2 and 44.5 grains the bolt lift was getting sticky.
I was shooting through the chrono at a steel silhouette at 600 yards. It was hitting the steel pig every time with ease. I need to get back out this week and print some groups on paper at 200 and 300 yards for further development. If the 107 SMK proves to be too much bullet for the 9 twist I'll try the 105 A-Max or 95gr SMK.

 

[Alien61]

Re: 243 Win & 107 SMK with a 26" 1/9 bbl?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DesertHK</div><div class="ubbcode-body">

When I switched over to Retumbo, I get better velocity. My best velocity is with N550 (3000 fps), but it's hard to find N550 these days, not to mention the cost.

</div></div>

hello community, first post here.)
does anyone have a luck with 105-Scenars and VV550? what loads you are using, because all my attempts still keyholing on 100m...

many thanks in advance.