I felt compelled to pass this info along to others that may own this safe . . .
Back in 2013 I purchased the 2014 vintage model of this 24 gun Winchester safe from Tractor Supply:
https://www.tractorsupply.com/tsc/pr..g?cm_vc=-10005
The electronic lock on this safe worked flawlessly for 2 years, and then I started having to enter the correct code twice almost every time in order to gain access. After about a month of needing to enter it twice it started requiring the code 3 times. At this point I realized there was an issue and I should contact Winchester. Unfortunately, I put it on the back burner until the lock would no longer accept our code at all. I replaced the battery thinking that was the issue, but it wasn't. We continued to enter the correct code sporadically for 5 days until we finally got lucky and it opened for us. And VERY lucky we were, as there are countless stories out there of owners with this safe never getting back in and needing to have it drilled. (and then obviously replaced)
Once we got it open I called Winchester support first and they immediately said that it was out of warranty and that my only recourse was to call a locksmith. I called a local safe locksmith and asked if he could swap out the electronic lock with a manual one. He said it was no problem, came and looked at it, and told me that it would likely be around $380, but that he would get back to me in 24-48 hours with specifics. After 72 hours of nothing, I called him and he made it clear that he didn't want the job.
At this point I pulled the locking mechanisms apart to figure out the make/model of the electronic lock and called LaGard, the manufacturer. The woman I spoke with was very forthcoming once I won her over with 20 minutes of idle chitchat . . . turns out that the Model 3710 electronic dial that these safes shipped with have a high rate of failure, particularly when any number is used multiple times in the sequence of your code. She also told me that 99/100 times an electronic lock failure is due to the dial/push-pad failing, not the actual locking unit. (The locking unit on this safe is LaGard part #LG4200) Since the unit was out of warranty she referred me to a company by the name of TimeMaster that specializes in lock replacement parts. This company only sells to distributors and locksmiths, so you need to make it clear that YOU are doing the work, otherwise they won't sell straight to the consumer.
I called up TimeMaster, and they told me right off the bat that the 3710 unit is a piece of shit and they fail all the time. He told me that the 3710 unit is no longer manufactured and that the 3715 is the replacement unit*. The only issue is that the 3710 mounts with bolts at 3 and 9 o'clock and the 3715 mounts at 6 and 12. Because of this, I ordered the newest and most improved version that mounts up with both patterns, part #3750*. That said, my Winchester safe provided mounting holes at 3/6/9/12, so you can save $30 and just go with 3715 as a replacement. Once I got the 3750 ($90 shipped), I replaced the unit and found that the locking mechanism, NOT the dial itself, retains the code and decides whether to unlock the safe or not. I can't say for certain which was the offending unit, but after testing, I felt confident that the issue was with the locking unit and not the dial. With that, I called TimeMaster back up and ordered part #LG4200. This ended up being $100 shipped, but after a week of trial, everything seems to be functioning at 100% on the very first try, every time.
*Other members have reported that model #3750 has been supplanted by model #5715 as of 2019. Model #5715 will fit if you reuse the screws from the original keypad. (Thank you, KSco, for this info!)
It should be noted that we're in/out of the safe at least 4 times a day, so although we suffered a catastrophic failure before 3 years, I imagine the lock will last longer for most people. That said, as soon as you start having to regularly input the code two or three times, DO NOT WAIT, BUY THE REPLACEMENT PARTS. Trust me, it's not worth not being able to get to your belongings. In my case, I bolted the safe into the floor, and the locksmith told me that it would have run us $400-500 to drill it open, plus the cost of disposal and obviously a new safe. So instead of the worst case of over $1,200, or the $380 the locksmith wanted, I spent ~$190 and did it myself. I will not publicly disclose how to dismantle and replace the lock, but if you're in a bind, PM me. I will note that the 3750 dial unit seems to be built MUCH better than the 3710 from both a security and craftsmanship standpoint, so I'm glad I upgraded. Please feel free to ask any questions regarding this safe, at this point I can probably answer the majority of them.
******* UPDATE *******
It's been four years since I installed the replacement parts and they're still working perfectly!