Range day

[Silentstalker]

Went to the range today. I have been working up some loads for my 7mm Rem Mag and my wife's 7mm-08.

The '08 really liked the 120 gr. Ballistic Tips. Shot my best group off the bench ever. I am a bowhunter just getting into reloading and rifle shooting. It is sure fun to see a gun perform and extremely frustrating when they don't!

The '08 is a LH Savage with accutrigger. Seems to really shoot well no matter what i put in it!

The 7mm Rem Mag is a Ruger m77 with a boyds stock on it. This 3/4 inch group is the best I have been able to get out of it so far with multiple powders. I always seem to have a flier. 2 pretty tight and 1 a short distance off.

Anyways, thought i would share since many of you have helped me with a lot of questions! Thanks!

Here are a few pics of the days best groups.

 

[DrMike]

Those are some fine groups. Any of those will serve you well in the field. Congratulations.

 

[JD338]

Nice shooting.
You should give RL22 a try in the 7mm Rem Mag.

JD338

 

[Silentstalker]

Thanks guy's. I am pretty happy with them so far. I am really falling in love with that 7mm-08. Might have to buy one for me too! That 120 gr. Ballistic tip is going to be incredible for antelope!

JD, I will have to try RL22 next. I have tried Retumbo and H4831sc so far. My best group is 3/4". My typical is about 1- 1 1/4. Plenty good for Hunting, but its fun to try to find the perfect load!

 

[FOTIS]

Like JD said Play with RL22 in the 7mm mag. If the velocity is OK with retumbo try seating depth variations.

What was velocity?

 

[nosler06]

Wow, you are getting me pretty excited to hit the range when I get a break in the weather. I like what I see with the Varget. I have recently switched to Varget, but have not yet got to the range to test it in my .308. Great shooting.

 

[Silentstalker]

I have no idea what the velocity is. I don't have a chrono. I have no signs of excessive pressure. I will try the other seating depths too. That is another thing I have not messed with yet.

 

[SJB358]

I have no idea what the velocity is. I don't have a chrono. I have no signs of excessive pressure. I will try the other seating depths too. That is another thing I have not messed with yet.

You'll do well to work with RL22 in your 7RM and 160's. I always start there. I have heard alot of good with Retumbo, but I bet you are not pushing a 160 where you can just yet.

Cartridge : 7 mm Rem. Mag.(CIP)
Bullet : .284, 160, Nosler PART SP 16327
Useable Case Capaci: 74.311 grain H2O = 4.825 cm³
Cartridge O.A.L. L6: 3.290 inch = 83.57 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon Retumbo

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

-10.0 99 68.40 2757 2700 42036 13224 98.8 1.402
-09.0 100 69.16 2791 2768 43574 13342 99.1 1.378
-08.0 102 69.92 2826 2837 45167 13450 99.4 1.354
-07.0 103 70.68 2860 2907 46841 13547 99.6 1.331
-06.0 104 71.44 2895 2977 48576 13633 99.8 1.308
-05.0 105 72.20 2929 3048 50384 13708 99.9 1.286
-04.0 106 72.96 2963 3120 52266 13771 100.0 1.264
-03.0 107 73.72 2997 3192 54230 13823 100.0 1.242
-02.0 108 74.48 3031 3264 56276 13871 100.0 1.221 ! Near Maximum !
-01.0 109 75.24 3065 3337 58414 13918 100.0 1.200 ! Near Maximum !
+00.0 110 76.00 3098 3410 60640 13963 100.0 1.179 ! Near Maximum !
+01.0 111 76.76 3131 3484 62972 14007 100.0 1.159 ! Near Maximum !
+02.0 113 77.52 3165 3558 65402 14049 100.0 1.139 !DANGEROUS LOAD-DO NOT USE!
+03.0 114 78.28 3198 3633 67946 14090 100.0 1.120 !DANGEROUS LOAD-DO NOT USE!
+04.0 115 79.04 3231 3708 70604 14130 100.0 1.101 !DANGEROUS LOAD-DO NOT USE!
+05.0 116 79.80 3263 3784 73387 14168 100.0 1.082 !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 110 76.00 3240 3729 75901 13367 100.0 1.079 !DANGEROUS LOAD-DO NOT USE!
Data for burning rate decreased by 10% relative to nominal value:
-Ba 110 76.00 2879 2944 48078 14301 97.4 1.310

 

[longwinters]

I love the 7m-08. With 120 BT's or 140 Accubonds mine is pure joy.

Long

 

[OU812]

The group looks great to me for the 7 mag but like others have suggested, RL-22 is most certainly worth a look see. Sure like the little 7 as well, good groups and good shooting.


Bill

 

[Silentstalker]

Thanks guys. It's winter cold right now but hope to get Out again next week after Christmas to shoot some more.

 

[Silentstalker]

Went out again to retest my best loads. It was bitter cold but i just had to go! 24 degrees with snow flurries towards the end.

My groups really disappointed me. I reshot my retumbo load in my 7 mm rem. and my 140 gr. Varget load in my 7mm08.

How much does cold weather affect groupings? One thing i noticed was the 1 st shot was drastically different than the rest. The barrels never really got hot but the cold barrel 1 st shot was up to 2 inches different impact. So, did the cold ruin my guns consistency or did it ruin me as a shooter today?

What has been your experience? I am thinking I will wait till spring or a good warm up before i shoot again.

 

[nvbroncrider]

Could be both. The other day I had very similar conditions and my first shots were all pretty far out of what my rifles were shooting.

 

[Silentstalker]

Good to know. I guess if your hunting very cold conditions you would need to sight in with a very cold barrel? That 1 st shot is the most important.

 

[nvbroncrider]

I don't think a half inch would matter or an inch. But if your 3-4 inches out I'd be concerned.

 

[Silentstalker]

So i just cant get loads in my 7 mm to shoot consistant and as a newby i was informed some of my troubles could be from me mixing brass. I have remington (20), several hundred winchester and about 10 federal i picked up along the way.

I just sorted them and found the odd brass was pretty evenly spaced among my winchester brass. I now havem seperated and am going to continue developing loads with the win. Brass.

How much deviation on impact should i expect from the 3 types. Am i grasping at straws to say this is why my loads dont shoot well consistently? I will shoot a group like the ones above and turn around and shoot a 2" group with the same load. I feel like the rest is very solid and my shooting is consistant...

 

[DrMike]

There can be considerable differences in pressure, and hence, in velocity, resulting differing POIs even in different lots of brass. When you throw in different manufacturers, the shift can be quite dramatic at times. You are well advised to keep the same lots if components, and assuredly the same manufacturers, whenever you are loading for accuracy.

 

[Silentstalker]

That would explain my eradic groups. I guess you live and learn. Thanks again!