My first handgun was a 1911, which I learned to shoot in the Jeff Cooper/Chuck Taylor manner, because that was what I was reading, and that is how I was mentored, by a student of Chuck Taylor. (I had not grown-up around firearms.) The best position for my weapon-hand thumb was forward, riding the safety. The thumb-forward support hand grip was not yet a thing, but I do not clearly remember exactly how I placed my thumb, other than remembering that its position evolved, over time. Eventually, I started using the thumb-forward support hand hold, influenced by the competition shooters, such as Rob Leatham.
Within a short time of buying that first 1911, however, in late 1983, I has hired by a big-city PD, and had to really, truly, seriously learn DA six-gunning. The curriculum was to shoot thumbs-down, and that is how I did it. So, for years, I shot 1911 pistols with my thumb riding the safety, and revolvers, and then later DA/SA autos, with my weapon-hand thumb locked-down. This continued, if I recall correctly, into the 2002-2004 time frame, when I used G22 Glock duty pistols.
Then, in 2004, I started using a SIG P229R duty pistol, and found that the thumb-forward support hand grip worked well, with the “drumstick” of my support-hand thumb firmly locked against the weapon. Of course, the weapon-hand thumb had to be forward, for this to work. So, I became a both-thumbs-forward shooter, when circumstances allowed. I worked straight nights, usually 10P-6A, so, much of the time, I had a hand-held light in my support hand, so, would default to the thumb-locked-down grip, at such times.
Then, in 2011, just before I reached age fifty, things started changing. My “strong” hand was not so strong, anymore, due to nerve damage and/or impingement, and arthritis became a factor. I could no longer trust my right hand to provide enough support, for reliable auto-loader function, with the wide-body SIG, unless I locked-down my support-hand thumb. I was not limp-wristing, so much as numb-thumbing. Notably, however, my left hand is not “weak,” as I was born left-handed, but right-armed, and have been functionally ambidextrous with most handguns. So, when firing two-handed lefty, with autos, I will still shoot thumbs-forward. I continued to carry right-hand primary,
Not long before the panic-demic, I had a numb-thumb incident with a previous-reliable 1911, and that caused me to stand-down my 1911 pistols, for primary defensive carry. I plan to experiment with 1911 shooting, with my thumb in positions other than riding the thumb safety. (I would still use a 1911 for fixed-position home defense, with the weapon in my healthier left hand.) None of my vetted 1911 pistols has an ambidextrous safety, for defensive carry.
A couple of years ago, I added a 1911 with ambidextrous safety levers, but the darn levers are not workable, as the huge “gas pedal” lever on the left side bears against the base knuckle of my left index finger, when gripping the weapon lefty, and, in right-hand mode, if I ride that huge safety lever, the web of my hand cannot properly interface with the grip safety. This is yet another reason for me to get away from riding the safety. (I have yet to decide whether to grind-away the offending “gas pedal.” It is a high-end pistol, so, perhaps, I should re-home the thing. I bought it pre-owned, so would not lose too much.)
Then, the panic-demic interrupted opportunities for regular training, and I eventually stood-down my Glocks as defensive carry weapons, because I need a substantial amount of live-fire training, with Glocks, to maintain the accuracy I want, at distance. I will still use Glocks for home dense, where the range is short.
I have experimented with thumbs-forward, with Glocks, but have generally defaulted to thumbs-down. My first round with Glock was 2002-2004, when I used G22 duty pistols, and a G29 during some personal time. I worked a Gen3 G17 back into my life, in 2012, in the hope that my then-chief would OK 9mm duty pistols, as .40 S&W, fired from my high-bore-axis P229, was really vexing my arthritis. It was late 2015, when I could finally carry a G17 on duty, and by then I had discovered the Gen4 fit my hands far better than Gen3.
I have never had good results with my thumbs pointing higher than horizontal, with any handgun. If my thumbs are not locked-down, then I have aligned one or both of them with the target.
Notably, having defaulted to revolvers, for carry, has not been a problem, for me, as I learned to LOVE long-strong DA shooting, with revolvers, in the Eighties, and never forsaken them. I kept carrying duty revolvers, for a numbers of years after I was able to transition to duty autos. Every time a duty autos would let me down, I would default right back to a duty sixgun, until a rule change in 1997 ended that. Revolvers are why my right hand remains relevant, for defensive shooting, as a revolver, with not-too-large grips, remains as viable, as ever, in my right hand; thumb firmly locked-down, of course.
