Edgun fps changing from day to day – hour to hour???
My Edgun came shooting @ 920fps (as recorded by my lighted chrony in the basement). A few days later, at the range, I felt like it was shooting more slowly. I didn’t have my chrony with me, but noticed that I had to hold over by an extra dot at 100 yards. When I got home, I tested the gun on my back porch in the shade – the chrony said 880 average. So, I upped the gun back to 910 average.
Today, I went to the range again, and the chrony said the gun was shooting at 950 average. I believed it because they pellets were laying down 1″ groups at 50 yards, and I know it can do better. When the gun got to 110 bar, and the chrony reported 910fps, the groups went back to MOA. I even went out to 100 yards, and shot two groups – one at 150bar (950fps) and one at 110bar (910fps). The one at 950 was just over 2″ – the one at 910 was my first sub MOA group with this gun.
When I got back home, I went to the backyard to dial the gun back down. I filled it to 180 bar and took a shot…912fps. Took another – 906fps….907…902…905…906….
What could be causing this? Batteries are fine in the chrony. I really think it is the gun. After you shoot it 500 times and make power adjustments, you get a feel for knowing the sound for each speed – or, at least I thought I had a feel.
The accuracy and chrony reading sure had a strong correlation. So, what could be causing this significant change in speed (40fps)?
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Why do you ask? Do I win a prize?!? 😆
I thought yes, but no 🙂 normal, ordinary Lothar Walther barrel.
Aloha, Mark
Mark, I’m using a predator shooting rest. It’s not the best, but it manages to fit the Edgun pretty decently (considering the “odd” shape of the stock).
Ed
Ser. No 2339
Why do you ask? Do I win a prize?!? 😆
What is the serial number of your Edun?
Ed
Thanks for the info. Ted, It’ll be a good starting point to find the sweet spot on my gun.
Last question, what kind of bag/rest are you using?
Aloha,
Mark
Mark,
130-190 bar is the sweet spot for my gun, tuned to shoot JSB 18’s at ~915fps. It’s pretty much one to the next in that range.
190-200 is pretty good too, with an occasional “hot” pellet in the 930fps range.
From 115-130 I get an odd “slow” one – about 20fps slower. Below 115, the fps starts to drop off steadily.
When I had it tuned to shoot at 880, the range went lower; all the way to 110 before the fps started to change.
Great shooting Ted. I’m glad the accuracy came back. I’ll be keeping an eye on the shot count and group size on my barrel. I’m still working on my first thousand.
I might have missed it but what is the sweet spot (fps/bars) on you Edgun? I haven’t had the chance to chrono my gun yet but my gun seems to settle down when the gauge reads around 180 bars.
Aloha,
Mark
50 YARDS:
The cleaning of the barrel seems to have done the trick. I shot a couple quick groups at the 50 yard range. I filled the gun to 200bar, and “broke it in” with 20 shots (right target). When I was satisfied it was hitting its mark, I took 5 shots at the target on the left. Solid. Now let’s move over to the 100 yard range…
100 YARDS:
I shot all groups using a mil-dot holdover. If I ever get serious about FT, I’ll dial the elevation adjuster. But, this gun is a hunter, and I need to learn how to be quick with my shots. The bottom right target was shot with a 5 dot holdover. The other three were shot with a 5 1/2 dot holdover (basically a dot at the top and bottom of the bullseye). The upper right target is a 10 shot group – the rest are 5 shots.
Considering I am NO field target shooter, these groups are very satisfying. I’d like to see what a “real” shooter could do with this gun. When I went out to retrieve the targets, I place fixed an empty 2.5″ pellet tin to the backstop. I proceeded to hit it over 30 times in a row, before missing it low when the pressure was at 115 bar. That is 30 dead rabbits at 100 yards! 🙂 The guy next to me at the range took 5 shots to hit it once with his 30-06. 🙂 I am very happy with my Edgun!
And I’ll be even happier as soon as Ed and Tony get me a proper stock. 😉
Thanks Ted am interested in the follow up groups tomorrow.
So, your Edgun (and the rest of your guns) does not lose any accuracy as you pour the rounds through the barrel? No change in POI? No flyers?
What about if you switch ammo? Ed recommends cleaning the barrel if you change things up.
I hope this doesn’t read like I’m saying you are wrong not to clean the barrel. I’m just curious how you do things. ❓
I’ve never polished the inleade on any rifles (I have had tuners do it for me). Do you simply use a dremmel with a felt tip with a bit of paste?
I have done some cleaning and testing but that is the only time I have
cleaned a barrel… Never cleaned one due to accuracy deterioration…I
do not polish the inlead…. Just the bore…No POI change that I can
see out to 80yds…. ….. I don’t change ammo unless I am doing initial
testing to see what flies the best….. My guns either get JSB 15.9gr or
JSB 18.1gr…..
Interesting, Mam. 💡
So, your Edgun (and the rest of your guns) does not lose any accuracy as you pour the rounds through the barrel? No change in POI? No flyers?
What about if you switch ammo? Ed recommends cleaning the barrel if you change things up.
I hope this doesn’t read like I’m saying you are wrong not to clean the barrel. I’m just curious how you do things. ❓
I’ve never polished the inleade on any rifles (I have had tuners do it for me). Do you simply use a dremmel with a felt tip with a bit of paste?
I polish all of my barrels, and crowns with fine valve grinding paste and then
fine automotive paint compound…. I haven’t cleaned a barrel yet….
Mark, I just finished cleaning the gun an hour ago (9:30pm). I hope to take it back to the range tomorrow to see if the cleaning makes an impact. It has to…that barrel was sooo dirty.
Do any of you long-time Edgun owners have any insight re: loss of accuracy and dirty barrels? Of course, it’s well known that a leaded barrel will be less accurate. I’m interested in how accuracy started to change/decrease as the barrel got dirty, as well as how many shots you can get in between cleanings.
Hey Ted, did you get a chance to shoot after cleaning? Did the groups start tightening up again? Haven’t gotten a chance to chrono the Edgun yet but as long as it’s grouping, I’m happy. Next week when I have more time I’ll try and run some over the chrono.
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Thanks Ted 😀