18" SPR...

[J Krammes]

I finally got some time to get out to do some shooting recently with some mixed results. I built the gun. It has a WhiteOak Armament 18" SPR barrel, Gieselle SSA-E trigger, Vortex Viper 6.5-20X50 in an AMD Recon mount. The barrel has a little over 100 rounds through it now. I got some pretty decent groups, but some not so good groups. I was shooting Blackhills 77gr white box (seconds). Most were right at 1" or just under. My best was .65". Some just erratic. Then I added the suppressor... I expected groups to at least stay at 1", but they did not. I was starting to get frustrated, so it may have been me. Any thought as to the inconsistent groups? I am working on getting set up for reloading so I am sure that will help.

The gun...


Best group...


Top group is unsuppressed (the square is 1"). Middle group was the first 5 fired with the suppressor on, then the bottom was the second 5 with suppressor. I ran out of ammo after that. No baffle strikes either. It was the first thing I checked.


Jeremy

[FromMyColdDeadHand]

I don't know that much about Blackhills whitebox ammo, but I'd try some known handloads or factory 'firsts' before I'd draw any real conclusions. I see on WOA site that the SPR barrel has a custom chamber, and not a Wylde chamber like the HighPower rifles. I wonder how it differs? From what I can glean from all the groups I've seen out of my rifles and one posted on the interwebs, the Wylde chamber likes .223 loadings of the 77gr SMK bullets, don't know if that will hold true for this barrel. Wouldn't hurt to try some lighter bullet loadings too.

Are you using something to hold the rifle, or a bipod and rear bag?

Nice stick by the way....

[ALCOAR]

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[BaileyMoto]

I completely agree with everything you said above.

*BUT* (you knew that was coming, right? lol), my only 'problem' is the industry standard, or lack there of, when it comes to the number of shots used for measuring accuracy.

Statistics likely dictate that the more shots you fire, the more your groups will grow in size, largely due in part to uncontrollable outside factors. I imagine that if one takes 100 3 shot groups, 100 5 shot groups, and 100 10 shot groups...their averages will increase from smallest to largest, respectively.

Since the 'industry standard' has essentially been 3 shots (but now a days its trended towards 5), then I feel it sort of throws a wrench in the mix when we start using 10 shots as the standard for comparison. If for so many years we have called rifles "1/2 MOA accuracy" based upon 3 and 5 shot groups....now suddenly we start using 10 shots as the standard, then would we have to pretty much invalidate all the data we have come to know as the standard? 1/2 MOA rifles of the last 20 years may likely no longer be 1/2 MOA rifles.

Personally, I also feel that a 10 shot group is a better system to use, as more points of measurement always helps eliminate outliers and 'luck'. With that said, I'd be just as comfortable with 5 shot groups, but averaged over a certain number of groups. An average of 5, 5 shot groups would probably be enough to convince me of the inherent accuracy of a rifle. Regardless of the number of shots, I think it's important to be able to say "I can shoot this size group at least 90% of the time".

Maybe we could come up with a formula for converting both 3 and 5 shot groups to '10 shot accuracy'? Heh.

[J Krammes]

Trident. I have been following you posts about your rifles. Alot of good reading. I actually wanted to do some 10 shot groups, but limited ammo prevented that during this outting. This was only the second time I fired this gun. I had moved the mount back and was using different ammo and was sighting it in. I know I have to shoot alot more and I do want to try some other ammo. I just need some dies and components to start reloading on the Dillon. This shooting was done on a bench with a rest at 100 yrds.

An average of 5, 5 shot groups would probably be enough to convince me of the inherent accuracy of a rifle.

This is pretty much what I have always used as a measure of accuracy, as has my dad.

Jeremy

[FromMyColdDeadHand]

Are these your knives, I couldn't get the link in your sig to work.

http://apocjkknives.blogspot.com/

What kind of bipod and rear support are you using?

5 is better than 3- especially when some has what they call a 'flyer' in every three shot group.

[ALCOAR]

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[J Krammes]

Are these your knives, I couldn't get the link in your sig to work.

http://apocjkknives.blogspot.com/

Yes, that is my site. That is wierd, the link works for me when I click it.

What kind of bipod and rear support are you using?

5 is better than 3- especially when some has what they call a 'flyer' in every three shot group.

I have a Harris bipod for it, but I was using a Caldwell bag for up front and a bag in back for this shooting. I don't subscribe to the Massad Ayoob way of measuring groups.

Trident, thanks. I will try shooting prone with the bipod next time. I will also give the V-Max a shot too. I have some 500 yrd shooting to do soon...

Jeremy

[Wolverine954]

Were you getting any mirage? I'd be surprised if you weren't since you shot suppressed and mentioned that you were getting frustrated - which implies maybe you were shooting fast/ getting hot.

That first group was real good. .650" is nothing to sneeze at!

Try several different factory loads and bullet types. The heavy stuff has the sex appeal, but as previously mentioned, you may be better off with a shorter, varmint type projectile at short range.

Nice rig!

[ALCOAR]

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