Group size with sandbags

For those who have a very nice accurate bullseye gun, what size of group should can you expect repeatedly when using sandbags. 
Say you shot four five round groups and took the average, and also for four ten round groups that took the average? 
Respectfully,
Wayne Van De Graaff - Oregon

With good ammo*, a good bullseye gun will group sub 3" at 50 yards in a 30 shot group.

*good projectile, consistent powder charge, ect.

I recently played with several flavors of 22LR ammo - CCI SV, which I usually shoot, and some high end stuff from RWS and Eley.  At 25 yds., I easily shot 1/2 to 3/4" 5 to 10 shot groups from a rest, into the X-ring.  Groups were ca. 1.5" at 50 yds.  I mention this because there are many variables involved from ammunition and gun quality to shooter ability.  A 22 is useful here, as it will more likely show shooter ability (or lack thereof) since good 22 ammo and guns will more likely show inherent precision and accuracy than a 45 or other.  Of course groups get larger, the more rounds one puts into them down range.  But whether one tests with 5 shot or ten shot groups, both should statistically predict the same population of shot dispersion - just the math is different.

This is my Hardball gun shooting 4.4 gr Bullseye behind a 185 Hornady XTP.  The two groups were because of my 73 year old eyes not able to hold focus on the front sight.  I would expect a ten shot group to be 7X or better “clean” at 25 yards with a rested hand held gun. 

Wobbley wrote: my 73 year old eyes  

I have only ever seen your avatar, (and an image of your shoe!) so I had no idea!

68 here, and just starting to see a difference in my shooting this year. A bit frustrating...

Great question--I've wondered the same because from sandbags (.45 bullseye gun) I always seem to have one shot out of five that I would call a "flyer" and would love to have my gun tested from a Ransom!

Many years ago when I was in shape I arm rested a .5" string at 50yds with my 41 and 900b ammo.  Ultradot sight.  Arms were rested across the box to the wrists.

Greetings,

Several years ago, I owned a Haemmerli SP-20 in 32 WadCutter.

The barrel is easily removed with this model.

I shot three ten shot groups with the barrel in a barrel tester. Then, three ten shot groups with the barrel back in the pistol.

I did have a 4X scope attached to the SP-20.

Laying the six targets side by side, it was hard to tell what method shot which group.

All groups sub-ten ring at 50 yards.

So, yes, with a sandbag rest you can get good results.

Cheers,

Dave

Very good information, thank you all!!

10 rounds LSWC at 50 yards rested, right after I mounted a new dot. (hence the need for sight adjustment)

Circled round was my error.

fc60 wrote:Greetings,

Several years ago, I owned a Haemmerli SP-20 in 32 WadCutter.

The barrel is easily removed with this model.

I shot three ten shot groups with the barrel in a barrel tester. Then, three ten shot groups with the barrel back in the pistol.

I did have a 4X scope attached to the SP-20.

Laying the six targets side by side, it was hard to tell what method shot which group.

All groups sub-ten ring at 50 yards.

So, yes, with a sandbag rest you can get good results.

Cheers,

Dave

 Dave after this coming weekend Regional I want to do some testing with some 200 gr swc and Bullseye at 50 yds. I have a Leupold VX-3 EER 2.5x 8 I can mount on it and I'll shoot off bags. I don't know if the gun will cycle the slide fully, would that make a difference in accurate testing?
 Stan

It depends a bit on the spring.  With that heavy of a scope, I’d doubt the gun will cycle so will need to be cycled manually.  If you draw the slide manually and then let it go from full retraction, at least the lockup will be as consistent as you a make it.  I wouldn’t use power bigger than 3 but you could try higher power and see if it helps.

Ashley, it's got a 10 lb spring in it now and I don't have anything lighter.
Stan

Springs lighter than 10 have inconsistent lockup, IMO.

A couple of hints affecting results:

It had been mentioned a number of times that the 1st shot from each magazine may be a "flyer." I believed that 2 of the 3  10 ring flyers were the 1st shots from each magazine. The 3rd could have been from human error or slight imperfections of the bullet. After all, handling during shipment may have caused surface dings. I was happy with the 7 X's as proof of a good load though.

Eye to red dot and bullseye must be as clear as possible. Outdated eyeglass prescriptions and eye health changes with our senior shooters may cause an unstable and inconsistent sight picture and hinder results. I noticed this as I became older.

One must continue with the best trigger finger control and with proper breathing control during each firing.

It was also mentioned that the load that gave the best results may not be the one we shoot the best with. Even though there were 7 X's, this was not a comfortable load for me.

My best load which gave consistent results of 100-8 to 9 X's with my pistol was the star 185g. LSWCHP with the sloppy black lube and with 3.8 Clays powder.....Bullet now extinct. This heavy black lube kept my barrel of my .45 clean for a very long time.

Senior moment……load for those shots was 4.0 BE  Zero 200g SWC

Lacking access to an RR and having iron sights on the vast majority of my guns I always felt that my results off sandbags did not reflect the true accuracy potential of my equipment. I also hated sandbag testing as I felt I would burn through a lot of ammo with little training value and still have no certainty about the results. When you stare at iron sights on the 50yd target for more than a few shots off bags, it becomes very hard to keep your focus. I still feel that way.

When I finally did get to do some Ransom Rest testing with a great setup (RR clamped to a very solid concrete base) I was pleased to learn the following.

1. My gut feeling about which loads were more accurate was correct. Now I'm not saying that I can tell the difference between an X-ring load and a 10-ring load just shooting them. I cannot. But the ones I felt were "good" were 10-ring loads, the ones I felt were "ok" were 9-ring loads, and the ones I had no confidence in were genuinely pretty darn bad including shots off repair center! It was not just me.

2. I really didn't have any X-ring loads or guns. I still don't. My best 10-shot group off the RR was 2". In my book that is pretty good and more than acceptable to shoot BE with but the guys with the 1.5" groups have something I don't. My test included Atlanta Arms ammo out of a quality BE 1911.

3. I took a known 10-ring capable load -- literally the leftovers from the exact same batch -- back to the sandbags and shot a 10-shot group with iron sights. To my amazement I shot 100 at 50 yards. I had not achieved that before. So I thought for a moment, wow, I truly am capable of imitating the Ransom Rest just with my eyes and trigger finger. Then I tried to do it again and I couldn't, then a couple tries later I did shoot another 10-ring sized group but it was slightly offset in placement on target despite no change to my sight settings. If I was testing different loads in that session I would possibly have drawn incorrect conclusions about which one was best, when really it's just the variation from group to group shooting off bags.

So my conclusion is, I really cannot shoot well enough off bags with iron sights to know which ammo is best, but I can shoot well enough to know when something is suitable for BE use vs. not suitable, and that's enough for me right now. I have since used a 2x scope on a 625 revolver to shoot some more sandbag groups and that setup I believe is much easier to get repeatable results with than iron sights.

DA/SA wrote:10 rounds LSWC at 50 yards rested, right after I mounted a new dot. (hence the need for sight adjustment)

Circled round was my error.

I neglected to add that this was small primer brass that has been reloaded too many times to count.

I add that for new shooters that are under the impression that new Starline brass and JHP is a requirement to shoot with any accuracy.