Need more Speed!!!

[sawgunner2001]

Gents,

First of all, specs of the rifle in question...
.243 Win
27" 1-8" twist Krieger SS

Now on to the meat and potatoes of what I'm here to ask y'all.

I got to run my loads over a chrono today. The following results are all new Lapua brass, CCI BR2's, 107gr SMK (moly), H4350, and computed on 5 shot groups. With my 40.5gr charge I had very slight ejector swipe on 1 casing. With the 41.0gr charge, I had very slight ejector swipe on 3 casings. I'd love to show you a picture, but I'm afraid that with the shitty camera that I have (and can't find) and how slight the swipe is, you wouldn't be able to see it. It isn't like some of the photo's I've seen here where it looks like the casing grew a nipple where the ejector hole was. Just an ever so slight mark, barely visible. Keeping in mind the temperature today was around 70-75 degrees (I'd like to be safe when it gets up to 95-100), how can I get more speed out of these things? I'd like to be around 3000-3050 fps, but I don't know how much more I can push it given the cool temps today. Should I load up 5 rds each of 41.5gr and 42.0gr and see what happens? I've never run into ejector swipe when reloading .308 before...I had flattened primers and sticky bolt lift, but not ejector swipe. Something new and intimidating I guess. Also, I don't know if this is of any concern, but the primers don't show any signs of pressure. Any insight would be greatly appreciated.

38.5gr

HI--->2777
LO--->2743
AVG-->2764
ES--->34
SD--->13

39.0gr

HI--->2789
LO--->2760
AVG-->2777
ES--->29
SD--->12

39.5gr

HI--->2812
LO--->2777
AVG-->2796
ES--->35
SD--->15

40.0gr (Grouped the best of the bunch...by far. Not once, but twice.)

HI--->2861
LO--->2836
AVG-->2848
ES--->25
SD--->9

40.5gr

HI--->2904
LO--->2867
AVG-->2881
ES--->37
SD--->14

41.0gr

HI--->2917
LO--->2898
AVG-->2913
ES--->19
SD--->8

 

[sawgunner2001]

Re: Need more Speed!!!

I guess it may also be pertinent to say that my OAL averaged out at 2.850". What I mean by averaged is they were all seated at the same depth, but the tips averaged out to be 2.850". I don't have one of those fancy things that measures to the ogive yet.

I have not yet experimented with varying the OAL. Wanted to get my powder charge figured out first.

Thanks Guys,

Saw

 

[sawgunner2001]

Re: Need more Speed!!!

For anyone who may be following this, I fired groups with 41.5 and 42.0grs H4350 (everything else remaining the same) today with the following velocity results;

41.5gr

HI--->2969
LO--->2956
AVG-->2961
ES--->13
SD--->5

42.0gr

HI--->3009
LO--->2930
AVG-->2974
ES--->79
SD--->29

Ejector swipe (when present) was no more noticable on these higher charges than before. Temps today were in the low 80's. I'm going to try loads with 42.5, 43.0, and 43.5 next time out.

Do these loads seem like they're moving slow for being fired in a 27" tube? I'm wondering if I should try another chronograph? That'll be easier said than done, however.

 

[ChadTRG42]

Re: Need more Speed!!!

Try R25, H1000. You need a slower powder for a little more speed. But if it's shooting good, stick with the H4350.

 

[lostriverproductions]

Re: Need more Speed!!!

I would try a slower burning powder.

 

[sawgunner2001]

Re: Need more Speed!!!

Picked up a pound of Re25 today. Any ideas on a starting charge wieght for 107(m) bullets? I see in the .260/.243/6.5x47 reloading thread guys are using 46-48gr with 115's.

 

[sawgunner2001]

Re: Need more Speed!!!

Tested 42.5 and 43.0gr H4350 and a BUNCH of Re25 loads this afternoon. Results follow (the Re25 were 3 shot groups vs the 5 rd groups of H4350);

H4350

42.5gr

HI--->3051
LO--->3016
AVG-->3028
ES--->35
SD--->15

43.0gr

HI--->3079
LO--->3051
AVG-->3069
ES--->28
SD--->11

These both started to exhibit more pressure signs as they probably should have at these extreme charge weights. I did have loads of 43.5 and 44.0gr loaded up, but didn't fire. Go figure, the 43.0gr load is at an accuracy node (I think). I don't plan on using it, though. Not with the results that I got from Re25 shown below which exhibited absolutely zero pressure signs throughout. Keep in mind these are 3 shot strings, so don't take the SD values so seriously (especially the 0.84 value on the last string).


Re25

45.0gr

HI--->2904
LO--->2801
AVG-->2849
ES--->103
SD--->51

45.5gr

HI--->2923
LO--->2892
AVG-->2902
ES--->31
SD--->17

46.0gr

HI--->2976
LO--->2923
AVG-->2956
ES--->52
SD--->28

46.5gr

HI--->3009
LO--->2976
AVG-->2996
ES--->33
SD--->17

47.0gr

HI--->3037
LO--->3016
AVG-->3025
ES--->21
SD--->10

47.5gr

HI--->3122
LO--->3100
AVG-->3110
ES--->22
SD--->11

48.0gr

HI--->3152
LO--->3144
AVG-->3149
ES--->8
SD--->0.84

I plan on re-testing the 4 higher charge weights again in 10 shot strings to test for accuracy. The most accurate wins. Now I've got to figure out what to do with 9 lbs of H4350. I must say that it did do very well at 40.0gr @ 2850 fps. I was just hoping for a little more speed out of it.

 

[steve123]

Re: Need more Speed!!!

That's alot faster!Maybe you can swap for some more R-25.

Steve

 

[DRAM40A1]

Re: Need more Speed!!!

SD of .84, damn, you definently need to do more testing here. I was going to suggest RE17. I got almost 3100 with the 115 in a 6XC. Worth a try......

 

[sawgunner2001]

Re: Need more Speed!!!

I thought about trying a 48.5gr charge of Re25, but I start to get compressed charges around 47.0 or 47.5gr. I am currently running 0.006" neck tension (its the only bushing I have...I need to get a bigger one). At 48.0 the powder comes right up to the bottom of the neck (shoulder area completely filled). I have a feeling that at 48.5 its gonna start pushing the bullets out of the case (which they may be already...I'm gonna measure tomorrow) unless I crimp, which I don't want to do. Anyways, I hope one of these Re25 loads proves to be less than 0.5 MOA so I don't have to try another powder. I've already got 121 bullets down the tube and haven't gotten the load I want to use figured out yet. Another powder would add probably another 60 rounds fired or so.

I did call Alliant yesterday morning to inquire about data for Re25 in the .243 and he got around to calling me today to tell me that there wasn't any, so I shared my experience with him. He thought it was very interesting.

 

[sawgunner2001]

Re: Need more Speed!!!

Well, finally got it figured out.

Quit testing LR loads at 100 yds.
Switched to 115gr BN coated DTAC
Use a slower powder (H1000 or Re25)

Groups minute of gnats ass at 200yds and beyond.

Final load is..........

Lapua brass neck sized with a .270" bushing (for 0.003" nk tension)
CCI BR2 primer
47.5gr H1000 (it was a little more accurate than the Re25 was)
115 BN coated DTAC seated at 2.850" COAL (0.030" jump)
2965fps at 75*F, 60' ASL

Fired a 3 round group today at 450yds while I was getting my long range dope that was exactly 1" outside to outside. It was the only group fired this afternoon. The rest of my shots were concentrated on getting my elevation out to 700yds.

 

[wnroscoe]

Re: Need more Speed!!!

1" outside to outside at 450 yards with a .243, thats .168" Moa Congrats, I know you're excited now.

Where can I get a rifle like that?

 

[sawgunner2001]

Re: Need more Speed!!!

Thanks Roscoe. Took a while, but you're absolutely right...I'm pumped. I can't wait to get a few more shots downrange at extended distance to see if I can hold that performance as well as the rifle can.

 

[former naval person]

Re: Need more Speed!!!

My GAP with 47.5 RL 25 does 1/4 minute with the 115 DTAC. Problem...puts holes in the 1/2 inch steel targets. Damn. JMHO

 

[sawgunner2001]

Re: Need more Speed!!!

I noticed that same thing when I fired that group at 450. My buddy's .308 was leaving splatter marks and I was leaving dents....deep ones.