I purchased a new Remington model 700 muzzle loader rifle way back in 2001....one of the first. Stainless steel with a black synthetic stock in .54 caliber. Immediately upon the purchase, I had the business (Mann's Sporting Goods, Pinckneyville, IL) owner and Remington factory rep--John Mann) to install a new Lyman #57 peep sight with different apertures. John is a skilled gunsmith and the peep sight was installed perfectly. A great addition to the rifle. I have used this weapon probably 12 to 15 times in Colorado during the black powder season and have always be impressed with the rifle. The peep sight has a huge ghost ring and three different sized opening adapters. You can call John Mann at this number (618-357-2911). His business is in southern Illinois. He does all of the factory work for Remington in our tri-state area. I have killed probably 10 cow elk with my Remington 700 in .54 caliber. I use the 518 grain No Excuses bullet; Blackhorn powder at 90 grains by volume, and a hot CCI 209 primer. Adding a peep sight improved my shooting ability hugely. Hope this true info helps you in your quest to put a peep sight on your 700 Remington M.L. rifle. Cow Tag