Uragan (updates as I learn the gun)

I haven't touched one yet but that appears to be the hammer spring adjuster. It's still not obvious from the pics I've seen, where the regulator sits. 

I'm one to find the lowest reg pressure at which a gun will shoot the disired power while having a lighter than average cocking/firing cycle. Sometimes that means more reg pressure, sometimes less..... (and I always depressurize the action and removed the bottle (I hope there is a valve in this big boy bottle) if adjusting the reg)

Ex... My Vulcan 2 .30's firing cycle feels like the valve is getting hit with a 3 pound hammer everytime I pull the trigger. I'd love to back that out a bit but I don't want to lose any power or consitency. When time permits, I'll back the spring tension off a little and test for a while. When I get a comfortable result, I'll see how much (if any) power I lost. If too much and the accuracy at distance changed, I'd then go to the reg and raise pressure by a small amount and see what happened. It's time consuming and iterative... I don't currently have a way to test the reg outside the gun and this has been a busy spring (oddly good growing season considering the weather here the past 2 years so I'm taking full advantage).

Without having even seen a Uragan yet, I can't even guess how I would do this. Well, if that's truelly the hammer spring adjuster than can guess at that part of the puzzle. Then again, if mine has a comfortable shot cycle and does well on power and shot count.... I prob won't touch it except to make sure I have the best spring tension for consistency, if needed.

My motivation for adjusting is to see what my Uragan can do with the .177 15.5 gr. NSA slugs moving 850-900 fps.

Click to expand...

What are you shooting now? (pellet vs speed) That would just give something to start guessing at between reg and hammer spring adjustments. Might be worth picking up a tin of JSB Beasts (16+grs if I remember correctly) if you don't have them. Heavier than the slug you mention buit may slide though the barrel easier so speeds would prob be close. I've had poor accuracy with Beasts in the guns I've tried them in but for $12 (add shipping if appropriate) it's worth the test before adjusting in my opinion.

Hmmm, looks like I have some work to do. Retailer's test looks awesome but it was only a handful of shoots. Testing with the pellet I'd like to use is pretty disappointing. Both accuracy and consistency (chrony - 35fps spread in 10 shots). Weather is not cooperating this afternoon so maybe more tomorrow, need to hang new targets. That said, I've maxed out my scope (brand new) so I might need to swap scopes and try from scratch again.

Had some time to occupy while waiting on the plumber this morning. Changing the scope resolved the accuracy... The scope I failed with is the one I actually want to use but it turns out the mounts are a little funky. I'll have to order a new pair and try again....

Chrony results are also better this morning. Can't explain that one but the lighting is a little better. Might be that simple.

Very comfortable in hand, cocking and firing cycle are like any sidelever Vulcan but this one feels a little more solid/stable/distinct both cocking and through the firing cycle from trigger to action noise. Bark is pretty tame with just the shroud but putting a spare Sumo on it made it downright friendly. I don't have normal backyard sound to worry about but I do shoot from an enclosed space and if it's quiet surrounded by 3.5 walls and a full ceiling odds are pretty good outside for a hard hitting .25.

Shot string after the plumbers are done. Well pump gave out, getting water back takes priority for a while.

I shot over the chrony for kind of a base line.

I'm shooting JSB Exact King Heavy MKII, 33.95gr .25...

My caveats here are:

I was tethered. The pressure change on the SCBA Tank was from approx. 220- bar to 214+ bar. It's tough to tell exactly.

I shot all 100 shots at the same target. More to make sure I was aiming over the chrony as consistently as possible than to judge results on my 55y target.

The wind is fluctuating from left to right. Stronger now that when I sighted the 2nd scope. Still, the target definitely shows the impact of wind fluctuations. (I may include that target in my next post).

So for now.....

33.95gr JSB's, unsorted, unweighed

100 shots, tethered from 220 bar.

Max (as delivered) 874fps

Min (as delivered) 861fps

Avg 866.8

Spread 13

STDev 3.2

Taget results are approx. 85 shots in 1inch vertical and 3 inch horizontal spread, The others are 'close" but farther flung. Winds from 5-30mph are more than I can deal with under these circumstances but I expect this woud be much better under good conditions (including e holding for wind at the minimum)....

I'll shoot a full fill (not tethered) tomorrow and post both full strings. Hoping to not even need to test the 25gr kings....

I'll point back to this in a post I'll make at the bottom after email decides to deliver my stuff... 

I'm editing this particular post to include a more complete TETHERED shot string. Goal was simply to have the most stable 100 shots I can manage since this gun is advertised at 110 shot on the 530 cc bottle. There are some interesting differences from a 'full' fill on bottle only (not-tethered).That post further down the thread.... Bottom line.... my specific gun shows a lot of potential for shot count vs power but it will need some tweaking....more in next posts/pages.