gunpatscorp.comSears Model 300 firing pinIf the Model 300 is the lever-action .30-30 that Sears sold in the '50s it's a part-for-part copy of a Winchester '94. In fact, Winchester probably made it to be sold under the Sears name. If that's the case, a firing pin for a Winchester '94 can be made to fit it. POST '64, not pre-64The Ted Williams/Sears 100 is a post-64 Winchester 94, and requires a post-64 firing pin. We do have them available. sales@countrygunsmith.net
Your sears ted williams model 100 is actually a winchester model 1894 rifle that was made by winchester for sears.You can find a firing pin at numrich gun parts corp.They can be found on the web.
Go to the Gun Digest bookstore and get the Assembly/Disassembly book for Sporting Rifles http://www.krausebooks.com/category/firearms_knives
They are $6.25 plus shipping from gunpartscorp.
Not possible to answer at long distance, but if there are light firing pin strikes on the primer, a dirty unlubed weapon would be a good first choice. There are spray gun cleaners that can clean gunk, burnt powder, and dried oil from the firing pin channel, and under extractors. Clean the chamber as well. After cleaning, lightly lubricate, and try again. If that does not fix the problem, then you may have a broken or weak firing pin spring, or a damaged firing pin, and need a trip to the gunsmith.
Use Winchester or Remmington 7.62X39 ammunition only. I have heard that the Federal 7.62X39 works well also. Any others may have problems with "dimples" or may damage the firing pin. The Hammer spring in the Mini is not as strong as an AK-47. J. F. in Florida
Your winchester model 1894 was made by winchester in 1953.
Proofhouse.com
Winchester 30-30 by any manufacturer will work for you.
Your winchester model 1894 rifle was made by winchester in 1981.
94 winchester 30\30 3503591
That Winchester is mfg. 1958