My New .22 Bullpup won’t group consistantly.
So I recently got my hands on a . Vulcan Bullpup in .22 cal. I’ve read that most are doing well with 18.13 gr JSBs and to be fair I haven’t tried them yet but they’re on order. I’ve tried several other pellets and can’t seem to keep my POI consistent. Some brands will print 5″ groups (if you can call them groups) at 40 yards and others a little better but certainly not acceptable. I did manage to shoot a couple of 1/2 groups with Crosman wadcutters but then even they started shooting erratically.
It appears that my POI will shift from one shooting session to the next. I’ve tried two different scopes thinking that I may have scope issues but no change. I cleaned the barrel and still no change. Wondering if anyone else has experienced anything similar and if so were you able to correct it?
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Nice shooting! :4:
Gel , sometimes it is the little things that we miss or over look that will turn out to be the problem .
FROM : THE BIRDMAN
[emoji6]
that is good info – glad to hear nothing wrong with the vulcan 🙂
I discovered that the scope rail was not tightened enough. I hope i resolved.
When viewing the photos below please keep in mind that I was shooting from a folding bridge table that wobbled like a drunken uncle at an open bar wedding and a 25lb sack of #4 lead shot for a sandbag.
1st magazine 11 shots @ 40 yards
2nd magazine 11 shots at 40 yards
3rd magazine 11 shots @ 40 yards ( My blue collar, grubby index finger included for scale purposes,)
I’ve heard of finicky guns but I never would’ve guessed that the difference could be so extreme. More than satisfied with the Vulcan’s capabilities after witnessing this.
The third group. Can’t demand more. Awesome
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There are a couple places in the action that can be a problem, but not be obvious. I would check…
1. Two bolts that hold the scope rail onto action are tight. The rail isn’t actually indexed. Its position is held purely by friction and its two bolts.
2. Shroud is on, but not too tight. Two finger tip tight is enough. Too snug and you might change barrel tension with temperature change.
Pull the action from the stock and check…
3. Eight bolts at bottom that hold trigger assembly to bottom of barrel/cylinder bracket are tight. If these are loose, the whole action can wiggle in the stock despite tightening the two action/stock bolts.
4. All barrel/cylinder bracket bolts are tight. You’ll need to remove both side plates to check them.
That covers most of the things that can mechanically shift the action. What’s left then are air discharge consistency and barrel/pellet issues.
Rule out air discharge issues by checking pellet velocities for consistency. If the velocities are inconsistent, investigate
a. Hammer setting. Does changing tension make velocities more consistent?
b. Is the hammer the current generation hammer that is designed to avoid hanging up in its guide?
c. Did someone oil or grease up the hammer? It should only be dry lubed.
d. Regulator issues? You’d need to pull regulator and check with a tester. Lots of work involved best left to Ernest.
Pellet/barrel issues…
It appears that my POI will shift from one shooting session to the next. I’ve tried two different scopes thinking that I may have scope issues but no change. I cleaned the barrel and still no change. Wondering if anyone else has experienced anything similar and if so were you able to correct it?
I’m experiencing the same. I thought it’s a scope issue. Also cleaned the barrel but didn’t improve much. I have deviations of poi from session to another. It’s driving me crazy.
Using jsb 18.1 grains and 14.xgrains
HW100 which is a legend, has plastic trigger blade. Have you heard any bitching about its plastic trigger?
Guys,,,
what is wrong with Plastic parts if it made well??!! … i had my friend’s Vulcan in my hand,,but in fact i didn’t feel that the trigger made from Plastic,,,
those two above cover parts are good and i don’t see anything wrong with them if they made in Taiwan… all depends on the quality …if the manufacturer asked for a good quality then it will not be a problem even the parts made in China .. (Evgeny; im not saying that you are making the parts in China,,plz don’t get me wrong,, )
I’d assume that the trigger is made in the CZech Republic as this is where the Vulcan is made.
Are you sure?
http://www.network54.com/Forum/79537/thread/1437084837/Vulcan+parts+made+in+Taiwan
No Shooter, I’m not sure. That’s what the term ” I’d assume” is meant to imply. Checked my trigger tonight and it is indeed plastic. I’m confident that it will serve it’s purpose without any issues. My problem with plastic on guns is simply a matter of preference. Just a little something that I don’t care for on a gun which otherwise continues to amaze me.
Those are just the top covers for the breach block and rear portion of barrel. They are not items that need super high tolerance. That said, they fit like a glove on my Vulcan. Not even an issue.
The plastic trigger blade isn’t a problem either. The only thing I wish is that it had an adjustable height, tilt, fore/aft position, but that has nothing to do with it being plastic. The rest of the trigger system is metal and fairly adjustable. I have mine set for 50 gm initial takeup (pseudo 1st stage) then a very short “2nd stage” that sharply releases at 230 gm.
My sear overlap is set to keep 2nd stage without creep, and does not discharge even after 4-5 light, balk firing “taps.” Over travel post firing is set to the least amount that freely allows trigger cocking. Pounding butt against ground and hitting with mallet doesn’t discharge the gun. That along with gun not firing with some “taps” of the trigger against 2nd stage helps me verify sear engagement is adequate. You can sear engagement smaller to to be more touchy, but easily becomes a safety issue. You can adjust all that easily on the Vulcan. There are more adjustable trigger mechanisms, but the Vulcan’s is not at all bad.
The vulcan trigger lets me easily feel the end of takeup (pseudo 1st stage) and predictably let the shot go when I want it without minimal trigger finger effort. Makes my POI more consistent when the POA is wavering due to my hold. Gun shoots well and hits the target. If it is off, it’s me that screwed up, not the trigger blade being made of plastic.
NB: Please don’t balk fire and assume the trigger is anywhere safe. Every balk fire tap can move the sear a tiny bit closer to firing. Always recock or fire into ground after a balk fire. BTW, that’s when the ROT switch comes in handy. Engage the ROT and BEFORE re-cocking to avoid double loaded pellets.
What are items 60 and 61
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FROM : THE BIRDMAN
Totally agree! 😉