Lapua 105 Scenar Testing,Results!!!!!!)

[6BR]

Hey guys, I just got back from the range. I did testing with the Lapua 105grn Scenar. We started shooting at 8:30 AM and finished at 11:00 AM. The Weather;

Temprature-50 to 70 degrees by 11:00 AM
Wind-3 to 5mph with an occasional 10mph gust.

Here are the components that were used today;

1. Lapua Brass-Fire Formed to Chamber, Primer Pockets Uniformed and Necks Sized with a .268 bushing for .002 tension on bullet.

2. Varget Powder

3. CCI 450 Primer

4. Lapua 105grn Scenar

5. OAL is 2.365- I am .005 into the lands

I shot 8, 5 shot groups at 100 yards. Each group was shot with Varget powder with a different powder charge with each group. Here are the results;

1. 30.0grns-5 Shot group measured-.071,AWESOME!!!!!!)

2. 30.1grns-5 Shot group measured-.212

3. 30.2grns-5 Shot group measured-.178

4. 30.3grns-5 Shot group measured-.112,AWESOME!!!!!)

5. 30.4grns-5 Shot group measured-.210

6. 30.5grns-5 Shot group measured-.480,I think I pulled this
one)

7. 30.6grns-5 Shot group measured-.347

8. 30.7grns 5 Shot group measured-.137,AWESOME!!!!!),Started to get pressure, however, I think I could go a little hotter if I wanted to). I stopped at this load.

I am very Impressed with this bullet. I will use 30.0grns with the 105grn Lapua Scenar. With a 5 shot group, at 100 yards, measuring .071, I can't complain. I was not able to test over a Chronograph, but I believe this load runs right at 2900fps. I am tempted to go with 30.7grns because the group measured .137 and this load would give me a lot more velocity which would make a difference at 800 yards. I am betting 30.7grns is close to 3000fps. However, this load would be a bit harder on brass and I don't think it would be worth the extra velocity. I will do some more testing with the 30.7grn load and see how it does compared to 30.0grn load, which measured .071, at 800 yards.

Overall, I am very very pleased with the 105grn Lapua Scenar. I was originally using the 105grn A-Max, however, the Scenar easily out performs the A-Max in regards to accuracy and wind deflection. The 105grn A-Max will expand much better than the 105grn Scenar, making it more desirable for varmint hunting. However, I will use the 105grn Scenar for long range varmint hunting due to it's accuracy and wind deflection capabilities. If your shooting squirrels or P-dogs, the 105grn Scenar will do the job on these little varmints. If you shoot larger varmints like Woodchucks or Groundhogs, I would recommend the 105grn A-Max.

I am going varmint hunting next weekend and will report on how the 105grn Scenar performs out to 800 yards. Here is the specs on my rifle for those who aren't familiar with it;
1. 6BR Match Chamber for Lapua Brass, .272 no-turn Neck
2. Stiller Predator Short Action Single Shot
3. Bartlein, 28', 1-8 twist, .236 bore, 5R, 1.250 STRT Barrel
4. McMillan Tooley MBR with lead added to rear
5. Jewel Trigger
6. Vais Muzzle brake
7. Stiller 20MOA Base
8. Nightforce 30mm Rings
9. Nightforce NXS 8x32x56mm w/MLR reticle
10. Total Weight-20 Lbs
 
I took pictures of the .071 and .112 groups, enjoy. Have great weekend and good shooting.

 

[Bob3700]

What length is your bbl?

Have you ever chrono'ed any of these loads?

How do you know that 30 gr of VGT is 2900 fps?

Just curious cause the 105 Lapua has a much longer bearing surface than a 105 Berger and that would decrease velocity and increase the pressures.

If you have chrono'ed, what brand is it?

That was some nice shooting by the way!

Thanks

Bob

 

[6BR]

Bob, I am using a Bartlein 28', 1-8 twist, .236 bore, 5R, 1.250 straight cylinder barrel.

As far as velocity, I am guessing it's in that range. I didn't use a chronograph, but I will use one next weekend and I will run that load over it to see what the actual velocity is.

 

[Forum Boss]

I shoot the 105 Scenars from a 6BR. My 27', .236 PacNor barrel is faster than average, based on results from factory ammo. In my gun, 30.0 grains of Varget averaged about 2860 fps, measured with a Shooting Chrony, which tends to run a little faster than a PVM or Oehler.

I kind of doubt the Orig. Poster is getting 2900 fps with 30.0 grains Varget... but the chronograph will tell.

I know he's got a super-accurate rifle, but I'm hoping he'll post some of those groups so I can measure them again with my OnTarget program. In the past I've found the program does a good job measuring very small groups, and you get a reading closer to actual match scoring.

It's interesting, I calculated his 8-target agg. at 0.218375' which is do-able, but still pretty spectacular.

 

[JHardy]

I have found that the same powders I use in my 308 Palma gun also work the best in my 6BR prone gun. In the 308, I found that the same charge of RL-15 gave me 63 fps more than Varget,made Palma 20). The reason that is interesting to me is that I also get much better fps, with accuracy, in my 6BR,set NRA 600 yd prone record since broken).

Something that will help when chambering your 6BR for near 6BRX and Dasher velocity: Neck size a case and take note of where the bushing stops on the neck. Take your bullet of choice and seat it to that line, and send it to your reamer grinder for a custom throated chamber.

You just may be shocked at the extra velocity you can get with RL-15 and CCI 450s over Varget out of the case that now has more powder capacity. After all, any seating depth past the bullet bearing surface/neck bushing area is wasted since the long neck of the 6BR allows you the option to throat longer.

The 3000 fps velocity with this set up out of a straight 6BR and a 31.5' 5C Broughton is real not imagined. With the BRX and Dasher, you have to do it,fps) with the case itself because the necks are shorter. On the other hand, a 6BR with an 40degree improved neck,but not pushed forward like the BRX or Dasher) which is throated as stated above, would be a very nice package -- more capacity via the throat and improved case.

I have done 3000 fps,two different Ohlers) without a lot of problems in a Gilkes Ross action with no ejector. Jason Baney has almost been there with a shorter barrel,around 2980 or something) shooting RL-15 and the same Clinch River 106 bullets,won the World Open).

Just food for thought as I know there are those who can't get out of the low 2800s with their 6BRs.

Jim Hardy

 

[6BR]

I measured all groups with my calipers, so they could be a bit larger or smaller. The computer program is more accurate. I have posted groups before, and my measurements were pretty close to what the computer program listed. I took pictures of the .071 and .112 groups. Here are those groups. If you need a better picture, so you can measure them, I will send them to you ASAP. Where can I send them? I am not making these groups up. My good friend is an excellent gun smith and he witnessed my groups. I was group testing my 6BR rifle with Varget and the 105grn Scenars, and we were pressure testing and fire forming his 6BR.

 

[6BR]

Hey guys, I have not received any information from the moderator regarding group size measurement from his computer group program. I am anxious to find out how they compare to the computer measurements. It sounds like I shot a pretty good 8 group agg. with my rifle yesterday. The interesting thing about each of these groups is that each group was shot with the same powder but with different powder charges. That's pretty spectacular and shows how accurate the 6BR is. Sure, you have to be able to shoot but this cartridge is so darn accurate, it's hard to mess up. I would like to know what the moderator finds, because I am going to start shooting 600/1000 yard bench rest and I want to know how I compare to other bench rest shooters and their rifles. I am really happy with how the bullet and rifle are performing. This is, with out a doubt, the most accurate rifle I have ever owned.

 

[Forum Boss]

6BR,

Thanks for posting the target. Looks pretty good.

REQUEST: Please send a bigger picture to mailbox@6mmBR.com

And also, please measure the heavy black sqaure on the target,I think it's 1' on the sides, but please confirm). The computer program needs a linear reference so calibrate its measurements.

If you don't have the targets anymore you could just measure the black box on a fresh target.

Thanks!

Here's initial processing, assuming square is 1'x1':

The bottom target might be a little smaller group, but I included the cut at 3 o'clock. There's certainly more than half a bullet diameter so it's got to be at least an 0.15 or so. Still mighty impressive!!!

 

[6BR]

Moderator, yes, I believe the square is 1'. Thanks for the compliments on the groups. I am pretty happy with my rifle. I will be doing 600 yard group testing, with the 105grn Scenar, soon. I am going to shoot in a comp. real soon, so I am really happy with the rifles performance. I am going to stick with the lighter 30.0 load because of how accurate it is.

 

[Toby Bradshaw]

I wouldn't be too quick to settle on a 600yd load based on 100yd testing. Vertical produced by variance in muzzle velocity can be insignificant at 100yd,if you have an accurate rifle, which you do!) but very pronounced at 600yd. Run some muzzle velocity numbers,say, 10, 25, and 50fps apart) through a ballistics program at 100yd and 600yd and you'll see what I mean.

And one 5-shot group per load is essentially meaningless when trying to identify the 'best' load at any distance. It's like trying to estimate the muzzle velocity of a load by chronographing 1 round -- an indicator, better than nothing, but a poor substitute for a decent sample size.

When you test at 600yd you might want to bring along your basic reloading gear so you can tune the vertical out of your groups. If you show up with just your '100yd load' you could be in for an unwelcome surprise.

Toby Bradshaw
baywingdb@comcast.net

 

[6BR]

Toby, thanks for the info. I am going to test the load at 600 yards. The main purpose of my rifle is for long range varmint hunting, however, I would like to try my hand at bench rest. Once again, thanks for the info.

 

[Toby Bradshaw]

Here's something I wrote about load development back when Al Gore had just invented the internet. Some of it is out of date, but the basic ideas are still useful,to me, anyway).

http://yarchive.net/gun/ammo/load_development.html

Good shooting.

Toby Bradshaw
baywingdb@comcast.net

 

[6BR]

Thanks Toby, I will check it out.

 

[Klong]

It woulld be interesting to see a repeat of the 2 best and the 2 worst groups to see if it is repeatable. It would also be interesting to see this repeated at 300 yards. Nice rifle and great shooting, thanks for sharing the inforamtion.

 

[6BR]

I am pretty confident in the 105grn Scenar at long range. It's a great bullet for long range shooting.

 

[6BR]

I am hopefully going to be able to put up some bench rest targets at 600 yards this weekend to test my rifle and the 105grn Scenar. I will report back with the results.