I purchased a LASERLYTE which fits in the bore at Wal Mart a year ago.
It claims to put rounds within four inches of the point of aim at one hundred yards. It has met or exceeded the claim.
Step 1 was to make sure the firearms held no ammunition and no ammunition was present.
The first rifle I tried it on was a Marlin 336 which I had installed a new scope. When nobody else was home, I put a target with a small dot on the bull down the hallway of my home. Following the directions I brought the crosshairs in alignment with the dot and lined it up with the target dot.
The second rifle was a Savage 110CL. I had fallen while out hunting shearing the screws on the rear base of the scope. The Savage had caused me fits at a range session because I had not discovered the broken screws. The rifle had been very accurate and suddenly I was chasing bullet holes all over the target. A gunsmith removed the broken screw and remounted the rear mount. This is a favorite rifle and I did not use it in the 2008 season because I was not satisfied with a pre-hunt range session a hunting partner and I had with it. I should note that I had put a new scope on it. A Remington 700 I had with me got the duty.
Before heading out on our hunting trip we stopped at a Wal Mart for some last minute supplies and I spotted the LASERLYTE and purchased it.
On the same day I did the 336 I did the Savage. I took special care with both rifles to get the crosshairs and the laser dot to match up.
On the range the Marlin was right where I wanted it and did not require any adjustment. The Savage was about three inches high and about two inches to the right. I made adjustments knowing I was going to back on the range with some hunting loads. The test rounds on this day were some 130-grain handloads from thirty years ago. The plan was to continue developing 140-grain Silvertip (old style) hunting loads.
Before returning to the range with the Silvertips I did checked the scope with the laser. The range day was not ideal because of wind gust up to 27 MPH. But the results were satisfactory.
In 1957 I my Dad gave me a Remington 760. Bore sighting a 760 or like rifle is a challenge. Ammunition was pricy on our limited budget and I resorted to cutting a mirror down and sliding it up in the magazine well to bore sight the rifle. Over the years my family, myself, and friends have burn a lot of ammunition sighting in different rifles. A lot of ammunition was expended that could have been used for general practice if we had a laser bore sighter. Over the years my methods have refined, but I feel the LASERLYTE was a good investment.