Hey Folks -- My first mod to my 1377 was adding the Crosman stock for some more stability. Using my +1 reading glasses helps me see the sights without the target being too blurry, but being so much closer to the rear sight took some getting used to. At any rate, what I've discovered after a few dozen practice shots is that the gun is not shooting high anymore. Anyone know how this could be true? Nothing else has changed. Same pellets, same distance, same targets, but with the Crosman stock my POA and POI are pretty much the same now (any deviation I'm sure is my own error). I had been considering building up the front sight to compensate for shooting high (as others have done), but now it doesn't seem to be a problem anymore. Ideas anyone?
Quote from: Moonray13 on January 15, 2014, 07:34:31 PM
Hey Folks -- My first mod to my 1377 was adding the Crosman stock for some more stability. Using my +1 reading glasses helps me see the sights without the target being too blurry, but being so much closer to the rear sight took some getting used to. At any rate, what I've discovered after a few dozen practice shots is that the gun is not shooting high anymore. Anyone know how this could be true? Nothing else has changed.
Something changed drastically - the way you are holding the gun. Anytime you change the way you hold a gun (i.e. offhand, rested, etc.), you should expect to re-zero for the new hold.
I considered that, Larry, but it doesn't seem to be enough of a change to make this big a difference. I'm still lining up my sights the same way. But I am very new to this, so what do I know? Thanks for the insight. :-*
What he means is you might be pulling up on the gun in pistol form, but with the extra support in rotation upward of the shoulder stock you aren't pulling up anymore.
Where is your eye in relation to the rear sight a) when used as a pistol and... b) with the carbine stock attached ? (how far in inches from the rear sight)
Any small change in alignment, spacing, line of sight etc, at the shooter position (you) results in significant changes at the target face (distance). The same as rotation of 1 degree at 1/2 inch from a center point and, 1 degree rotation 100 inches away from the center point, measured (linear). The 1 degree increments have huge distance bewteen them out at 100 inches, and they are nearly immeasurable near the center point.
Your observations and corrections in sighting and final POI bewteen the two forms of gun (carbine vs pistol) are not unusual, at all.
It's even possible, although unlikely, that recoil could be a factor.
A pistol ( powder burning type) moves through an arc as the bullet travels down the barrel.
With a stock, it would move less, rise less, bullet would impact lower.
I am interested in your comment about reading glasses.
I recently started shooting after a long hiatus.
Are you using intermediate glasses?
I have been able to get a scope in focus.
If you use 1.00 for iron sights, is that the same as you use for reading?
I just started using +1 reading glasses for shooting. My regular readers for computer or Kindle are 1.75 or 2.0, both of which are too strong and make my target too blurry to see. The +1 version makes the front sight sharp, with the rear notch and target only slightly blurry. It's working so far, although I find at 20-feet or closer, it doesn't make much difference and I can shoot accurately without the glasses at all.
There's probably a difference of about a foot between where my eye is in relation to the rear sight on the carbine version vs. the pistol version. It makes sense that that difference could be a major factor in accuracy. Didn't think of that before.
Man, you guys area really helpful. :)
By the way, I am truly amazed at the accuracy improvement with the Crosman stock. From a rested seated position at about 20 feet I'm getting groups that were impossible for me before. I knew the stock would help, but this is impressive. I love this little gun.
Quote from: Moonray13 on January 15, 2014, 11:45:40 PM
By the way, I am truly amazed at the accuracy improvement with the Crosman stock. From a rested seated position at about 20 feet I'm getting groups that were impossible for me before. I knew the stock would help, but this is impressive. I love this little gun.
Moonray, I'm not surprised, I shoot my 2289 Backpacker with the stock rear peep sight and a Tru-glo front sight and plow 5 pellets in one .50" hole at 10 meters, with glasses and with 61 years of livin! The carbine arrangement makes a very stable platform. Have you done any trigger mods to your gun? Other than sighting correctly and good shooting manners, this is the next, most important thing you can do to aid accuracy.
Quote from: BDS on January 15, 2014, 11:51:02 PM
Have you done any trigger mods to your gun? Other than sighting correctly and good shooting manners, this is the next, most important thing you can do to aid accuracy.
X2 on what Brian has said. Trigger work will make it yet another new gun for you.
Carl
No trigger work yet. Compressing the spring or cutting off a loop looks like the easiest thing to do and I've watched a few videos on YouTube, but I'm not real confident in my abilities. The spring certainly looked easily accessible when I took off the grips to install the Crosman stock, so maybe that will be next. We'll see. It's certainly a good feeling when a change increases the gun's already considerable ability.
I highly suggest just squeezing the spring, it makes a very nice improvement, and if you want to go back how it was, just stretch it back out... If you cut the spring, it gets stiffer (although there is less preload, so still softer than stock), so I like the squishing solution best, or like others do get a cheap spring from the hardware store...
Or.... cut it down and get 50 cents worth of small, thin brass washers at the ACE store and just shim the post under the spring till your happy. The test is how light a pull you can achieve and still have the trigger return 90%-100% to home position and have the gun cock and fully engage the hammer. With washers, you can test in increments and its super easy.
Completely replacing the spring helps. I have a light, thin one in my gun. Certainly helps gets better groups at a distance.
Quote from: BDS on January 16, 2014, 03:17:04 PM
Or.... cut it down and get 50 cents worth of small, thin brass washers at the ACE store and just shim the post under the spring till your happy. The test is how light a pull you can achieve and still have the trigger return 90%-100% to home position and have the gun cock and fully engage the hammer. With washers, you can test in increments and its super easy.
Same method here but I replace the springs w/ a much lighter one..I usually have the spring maker fab three same height springs but w/ different thickness/tensions.
Quote from: jSan22 on January 16, 2014, 04:15:48 PM
Completely replacing the spring helps. I have a light, thin one in my gun. Certainly helps gets better groups at a distance.
Same here, I got one for 50 cents at Ace Hardware. Replacing the spring only requires removing one screw on the grip to access it. If a moron like me can do it, you'll have no problem.
I just squeezed mine and torched with a bic for a quick second...
on my 1322 I got it just right
on the PC77 I got it to light and it was firing while pumping so I stretched it back out just a touch and it has passed the impact test and has not pre fired again.