You know how your wife buys a new trash can for the kitchen, and it doesn’t match the front of the old refrigerator that you’ve been talking about replacing for several years? So, you buy a new fridge, but you want this one to have an ice dispenser in the door; so, you hire a plumber to run the water lines; as long as he’s there, you decide it’s time to replace the chipped sink with a new stainless-steel double sink; but as long as he’s under there, you might as well have him replace the water supply lines and the waste pipes. Then, your wife doesn’t like how the new sink looks against the old green Formica counters, and she wants those granite countertops you’ve been promising her ever since you forgot your 17th anniversary; but the new countertops won’t look right on the old painted cabinets, so you decide on some Scandinavian teak cabinets with glass doors; and now the chipped dishes look out of place. [Note from Edith: This is hypothetical. It's not a true story about us!]
Today is the day you find how I improved the accuracy of the Air Venturi Bronco rifle I’m testing with the Bronco Target Sight kit. I asked you to guess what I did to get better groups, but only Fred of PRoNJ got it right. I thought this would be a straightforward test and that one range session was all I needed for this rifle. After all, I already did a 7-part report on the gun, so there’s been plenty of time to get to know how it shoots. In fact, I even installed a Williams peep sight on the gun, so I even know how it shoots with that. This was just supposed to be a test of the Bronco Target Sight kit and nothing more. But man plans, and God laughs!
We get requests all the time for basic maintenance articles and fundamental articles about how to diagnose an airgun and make it shoot better. Often, I refer readers to blog reports I’ve done in the past, but today (and tomorrow!) is a blog report with something for almost everyone. It started out as a simple test of my Air Venturi Bronco rifle with different sights, but it blossomed in several different directions — answering many questions and raising issues about which many readers have indicated an interest in the past.
I didn’t plan on this report turning out the way it did. This special two-part report (today and tomorrow) is a serendipitous journey of airgun discovery. It began when I mounted the optional Bronco Target Sight kit on my rifle and thought I would be demonstrating just how accurate a Bronco can be. (The Bronco is also sold with the target sight kit installed.)
Today’s test is shooting the Crosman MAR177 at 25 yards, both with and without the magazine. We’ll also shoot it with the best wadcutter target pellets and the best domed pellets to see what differences there are.
Rather than shoot the rifle myself, I let Mac shoot it this time. He is the better rifle shot between us, and I just wanted to see what the rifle would be like in his hands. He shot it off a bag rest at 25 yards indoors. Ten pellets were shot from the magazine, then another 10 of the same pellet were shot using the single-shot tray. Mac tested both domed and wadcutter pellets, so we get to compare the relative accuracy of both today. And the results did not turn out as I expected.
Today, we’ll look at the Crosman MAR177 upper shooting domed pellets at 25 yards. I’ll be using the 10-shot magazine, so we’ll get to see that in action, as well. I’ll tell you right now that today was a learning day that spawned another report that’s still to come. Read on to learn what it is.
As you know, the Crosman upper receiver is attached to a lower receiver that I built on a Rock River Arms lower receiver shell. I used Rock River parts, and the trigger is an upgraded two-stage National Match trigger, also from Rock River.
Crosman’s new MAR177 upper is big news! This view shows the front sight properly oriented.
Today is the first accuracy test day for the Crosman MAR177 upper, so let’s see how this baby shoots. Blog reader Darth Cossack pointed out that I had mounted the front sight backwards in the last report, so I fixed that for today’s photo. It wouldn’t have mattered from a shooting standpoint, but we do want the gun to look right.
On this AR-15, both the front sight and the rear sight adjust for elevation, while the rear sight also adjusts for windage. The front sight requires a sight adjustment tool that I don’t have and didn’t see packed with the upper. You can also use the point of a 5.56mm military round, which I have an abundance of, but doing it that way is very laborious. I’m hoping the rear sight adjustments will take care of everything that’s needed.
Today’s report is about mounting the new Bronco Target Sight kit on an Air Venturi Bronco and seeing how it works. The kit consists of a peep sight for the rear and four riser plates with two long screws to raise the front sight high enough to work with the rear.
I tested the Bronco extensively in 2010 and wrote seven reports about it then. If you’ve been a reader for some time, you may remember that I even mounted a Williams peep sight on the rifle and tested it for you. So, today’s question isn’t whether the rifle can shoot with a peep, but rather how this new sight and riser plate set attaches and works with the gun.