This is posted over at RimfireCentral but I thought it might help people that come to this forum to know where to get these bushings.
I have all three types of bushings (Sam’s, BAM’s, and Tandemkross’), a Ruger Mark III 22/45 6 7/8 Hunter, and here are my thoughts regarding each one of these:

Most of the following pictures are just thumbnails and if you click on them, you will see a larger picture.
FIRST THINGS FIRST:
This is one of the easiest and one of the best modifications that you can do with your Ruger Mark III (including 22/45 and LITE) series pistol.
In other words, what I’m writing this post about is just concerning Mark III types of pistols (and specifically anything with a Mark III hammer):
If you don't know what you have, this may help: http://www.guntalk-online.com/forum/viewtopic.php?t=934
If you have a Mark II and want to replace your hammer bushing for a better trigger feel, go check out http://www.clarkcustomguns.com/ or http://www.volquartsen.com/ because they make bushings for the Mark II hammers. Again, everything from here on out is taking strictly about Mark III pistols.
Special thanks to Bullseye for being the originator of the Mark III design for the bushing.
Why replace the stock hammer bushing/magazine disconnect:
When you replace the stock hammer bushing, you will completely remove the stupid magazine disconnect as well as shown in this picture from Bullseye’s website guntalk-online.com:
If you don’t know what a magazine disconnect is: http://en.wikipedia.org/wiki/Magazine_disconnect#Magazine_disconnects
WHAT THIS MODIFICATION DOES:
WHERE DO I GET ONE AND WHICH ONE? NOTE: These were the 3 manufacturers that actually replied to my review request. These are in order as they were available to the public.
___________________________________________________________________________________________________________________________________________
Sam Lam’s Bushing:

$12.00 shipped. Made of O1 tool steel.
Sam is a great guy and lives in Toronto Canada. Basically you just send him an email at [email protected] and he quickly responds with his mailing address. You then send him either cash or check through the mail and about 2+ weeks later, you will receive your bushing (protected by card-stalk and tape) in a regular mail envelope. When I received mine, I was actually surprised that the mail processing machine rollers didn’t press or damage the bushing right out of the envelope. I guess Sam has sent enough to the USA and understands exactly what it needs to get by. He's been doing this for many years now.
Sam is a standup guy and stands behind every bushing he sells. I’ve even heard of a customer sending him cash, and it unfortunately got lost in the mail, and yet Sam still sent him the bushing.
What does Sam do that is absolutely awesome? Ruger tolerances vary quite a bit, and most people don't know, but Sam will also make you a CUSTOM bushing to precisely fit YOUR hammer and pin if you send them to him. Same charge and turnaround time.
UPDATE: Sam will now accept PayPal to the email address above. This is great since it cuts the shipping time in almost half.
___________________________________________________________________________________________________________________________________________
BAM Bushing


$15.00 shipped. Made of 304 Stainless Steel.
“BAM” are the initials of a great guy in Michigan. The perk about him is that he is an active member and sponsor at RFC and is very helpful. Another nice thing is that he has an actual website (http://bushing.webs.com/) where you can quickly order from and even go through a step by step picture guide on how to install a bushing. I personally believe that this is the most helpful online guide to installing these bushings.
BAM is easy to contact either here or through email if you ever need any help installing his bushing.
His online website is a PayPal web store but feel free to email him at [email protected] if you prefer another form of payment. Shipping is free from Michigan to US addresses and he will try to get parts out within a business day of purchase. Extremely fast shipping, provides tracking number, and has professional packaging (bubble wrap in a mailer envelope).

BAM offers an official, written Lifetime Guarantee on his product as well as many ways to contact him if you ever need help installing his or any other bushing.
BAM’s bushing is stated to be slightly larger than the factory part and thus the resulting tight fit will reduce or eliminate the trigger slop that is caused by the loose factory bushing. This sometimes requires buyers to literally freeze their bushing overnight in the freezer so that the metal will shrink just enough to fit snugly within the hammer. Some users swear by this tighter fit. (The hammer doesn't pivot on the bushing. Its the hammer+bushing that pivots on the hammer pivot pin.)
___________________________________________________________________________________________________________________________________________
I have all three types of bushings (Sam’s, BAM’s, and Tandemkross’), a Ruger Mark III 22/45 6 7/8 Hunter, and here are my thoughts regarding each one of these:

Most of the following pictures are just thumbnails and if you click on them, you will see a larger picture.
FIRST THINGS FIRST:
This is one of the easiest and one of the best modifications that you can do with your Ruger Mark III (including 22/45 and LITE) series pistol.
In other words, what I’m writing this post about is just concerning Mark III types of pistols (and specifically anything with a Mark III hammer):
- MKIII
- MKIII 22-45
- MKIII 22-45 Competition
- MKIII 22-45 Government Target
- MKIII 22-45 Target
- MKIII Competition
- MKIII Government Target
- MKIII Target
- MKIII LITE
- MKIII Hunter
If you don't know what you have, this may help: http://www.guntalk-online.com/forum/viewtopic.php?t=934
If you have a Mark II and want to replace your hammer bushing for a better trigger feel, go check out http://www.clarkcustomguns.com/ or http://www.volquartsen.com/ because they make bushings for the Mark II hammers. Again, everything from here on out is taking strictly about Mark III pistols.
Special thanks to Bullseye for being the originator of the Mark III design for the bushing.
Why replace the stock hammer bushing/magazine disconnect:
When you replace the stock hammer bushing, you will completely remove the stupid magazine disconnect as well as shown in this picture from Bullseye’s website guntalk-online.com:

If you don’t know what a magazine disconnect is: http://en.wikipedia.org/wiki/Magazine_disconnect#Magazine_disconnects
WHAT THIS MODIFICATION DOES:
- Magazines Fly Right Out! No more prying out bound up magazines after hitting the release button.
- Simplify Disassembly and Reassembly - No Magazine insertion/removal steps required
- Clean Up Trigger Slop. Note: The best thing available to really reduce your trigger pull weight is installing a Volqartsen target sear and an adjustable target trigger.
- Fewer Parts Simplifies Detail Strip
WHERE DO I GET ONE AND WHICH ONE? NOTE: These were the 3 manufacturers that actually replied to my review request. These are in order as they were available to the public.
___________________________________________________________________________________________________________________________________________
Sam Lam’s Bushing:

$12.00 shipped. Made of O1 tool steel.
Sam is a great guy and lives in Toronto Canada. Basically you just send him an email at [email protected] and he quickly responds with his mailing address. You then send him either cash or check through the mail and about 2+ weeks later, you will receive your bushing (protected by card-stalk and tape) in a regular mail envelope. When I received mine, I was actually surprised that the mail processing machine rollers didn’t press or damage the bushing right out of the envelope. I guess Sam has sent enough to the USA and understands exactly what it needs to get by. He's been doing this for many years now.
Sam is a standup guy and stands behind every bushing he sells. I’ve even heard of a customer sending him cash, and it unfortunately got lost in the mail, and yet Sam still sent him the bushing.
What does Sam do that is absolutely awesome? Ruger tolerances vary quite a bit, and most people don't know, but Sam will also make you a CUSTOM bushing to precisely fit YOUR hammer and pin if you send them to him. Same charge and turnaround time.
UPDATE: Sam will now accept PayPal to the email address above. This is great since it cuts the shipping time in almost half.
___________________________________________________________________________________________________________________________________________
BAM Bushing


$15.00 shipped. Made of 304 Stainless Steel.
“BAM” are the initials of a great guy in Michigan. The perk about him is that he is an active member and sponsor at RFC and is very helpful. Another nice thing is that he has an actual website (http://bushing.webs.com/) where you can quickly order from and even go through a step by step picture guide on how to install a bushing. I personally believe that this is the most helpful online guide to installing these bushings.
BAM is easy to contact either here or through email if you ever need any help installing his bushing.
His online website is a PayPal web store but feel free to email him at [email protected] if you prefer another form of payment. Shipping is free from Michigan to US addresses and he will try to get parts out within a business day of purchase. Extremely fast shipping, provides tracking number, and has professional packaging (bubble wrap in a mailer envelope).

BAM offers an official, written Lifetime Guarantee on his product as well as many ways to contact him if you ever need help installing his or any other bushing.
BAM’s bushing is stated to be slightly larger than the factory part and thus the resulting tight fit will reduce or eliminate the trigger slop that is caused by the loose factory bushing. This sometimes requires buyers to literally freeze their bushing overnight in the freezer so that the metal will shrink just enough to fit snugly within the hammer. Some users swear by this tighter fit. (The hammer doesn't pivot on the bushing. Its the hammer+bushing that pivots on the hammer pivot pin.)
___________________________________________________________________________________________________________________________________________