1. What is the thread pitch of your machine screw swivel studs?


The most common thread pitch of our machine screw swivel studs is 10-32.


  1. What is the thread pitch of your push button bases?


The thread pitch of our threaded push button bases is 9/16-18 UNF.  For assistance in their installation, please refer to our Push Button Base Installation Guide.


  1. Do I need to use glue or anything when I install a push button base?


The use of a light coat of two-part epoxy on the threads is optional, but recommended. Here is a helpful link for installing push button swivel bases: Push Button Swivel Base Installation


  1. Do you make swivel studs in stainless steel?


No.  We do however offer our swivel sets with a satin nickel finish.


  1. Can I order products from your web site?


YES! But there are many physical and on-line retailers that do carry our product line and we encourage you to support them.


  1. What if my local sporting goods store doesn’t carry your products or I can’t find them through an on-line retailer?


Chances are that your local sporting goods store is a customer of one of our authorized distributors and they can special order the item for you. If that doesn’t work, you can still order from us online!


  1. Are all your products made in America?


Yes! All of our products are made right here in our Wood Village, Oregon facility.


  1. Are you folks a division of Uncle Mike’s?


No. GrovTec US, Inc. began business in May, 2006 after acquiring machinery from a company that ceased domestic swivel manufacturing to source their products overseas. GrovTec US, Inc. is an independent, privately owned company dedicated to bringing you high quality, innovative products made right here in our Wood Village, Oregon manufacturing facility.


  1. How strong are your swivels?


A recent test of our standard 1" locking swivels pulled tested to withhold tension over 500 pounds and our heavy duty 1-1/4" push button swivel rated even stronger, holding over 584 pounds of tension.


  1. Do you make a mag cap for the Beretta A391 Xtrema?


No. We manufacture a push button magazine cap for the Beretta AL391 Urika which uses a different mag cap.


  1. I have an old lever-action rifle with a tubular magazine. Can I put a sling on it?


Yes. After selecting the correct size, you can use one of our barrel band swivel sets to mount a swivel on your magazine tube. Barrel band selection chart


  1. I purchased your GTSW-40 Barrel band swivel set for my .22 rifle, what is the piece of 1-1/4” x 3/8” black plastic that was included in the kit used for?


The plastic strip can be installed between the barrel band and the magazine tube. This piece can be used as a spacer shim to ensure a tight fit of the barrel band or as a protector to prevent any scratching on a firearm with expensive bluing.


  1. I am in need of a Split Band swivel set to fit a O/U 20Ga. shotgun barrel .703 in diameter. Do you or could you make a set to fit .675 to .725 Dia. for this gun?


 Yes, the diameter you mention would be our GTSW302. You may find your correct selection for a barrel band swivel set by reviewing our barrel band selection chart located here: Barrel band selection chart


  1. Do I have to worry about a barrel band swivel set coming off the barrel or magazine tube?


Absolutely not, our barrel bands are of a proven design that when properly fitted, will provide you years of rugged, dependable service.  Here is a hint for installation that has worked well for others:  When assembling around the barrel or magazine tube, do not tighten the upper screw all the way at first.  Just put it in finger tight.  Leave a slight gap about the thickness of a credit card between the two halves and then tighten the lower hollow screw very snug.  Then tighten the upper hex screw.  By leaving a small gap with the upper screw that allows it to work as a pivot point to tighten the barrel band by spreading the band with the lower hollow screw.  Then when the hollow screw is snug in place, then go ahead and tighten the upper screw and you’re done.


  1. I have a new Browning BLR, how come I can’t find a hammer extension for it?


The new Browning BLR has a folding hammer that provides an added measure of safety which the addition of a hammer extension may interfere with. Neither Grovtec, nor Browning recommends the use of a hammer extension on the new BLR.


  1. How do I install your wood screw studs?


Drill a 5/32” hole slightly longer than the length of the wood screw stud you are installing (i.e. for a ½” wood screw, drill a 9/16” deep hole.). Then countersink a 7/32” hole 1/8” deep into the original hole.  You will find that our GTHM-286 Sling Swivel Stud Installation Tool will make it much easier to install your swivel studs.


  1. How do I install a sling?



Slide the top piece of web through the metal keeper, slide a swivel onto the web. Fold the webbing down and feed web back through the underside of the keeper. Repeat the process for the lower section of webbing and adjust for comfortable length.


  1. How can I become a Grovtec dealer?


We sell through distributors. Chances are that if you are a dealer or a retailer, you already have an account with one of our distributors. To receive dealer pricing, please contact us to receive our list of authorized Grovtec distributors. 


  1. I need to have some custom parts machined. Do you manufacture OEM parts for other companies also?


Yes. Beginning with your custom part prints, drawings or sample for evaluation by our engineering team, we can manufacture machined parts for those who do not have their own capabilities. We produce OEM parts for many major manufacturers in the firearms industry. You can also visit our GrovTec Machining website at www.grovtecmachining.com.


  1. Does your GTSW-299 Multi Adaptor stud fit in normal flush cups?


Yes. The multi-adaptor is designed to fill all standard flush cups (Also known as push button swivel bases).


  1. I have a 12 gauge Remington 870 Express. I see you have two types of magazine caps for Remington’s. Which magazine cap should I use and how can I tell the difference?


You can use either our GTSW-34 or our GTSW-296 push button magazine cap. These are designed specifically for the 870 Express. You can tell the difference by looking at the inside of the magazine cap. The cap for the 870 Express™ has internal detent slots on the inside of the cap. The magazine cap for the 870 Wingmaster™ has dimples on the lip of mag cap.


  1. What is the thread pitch of your GTSW26? I have a Ithaca Model 37 and it doesn’t have a threaded hole on the barrel lug so I have to drill and tap it.


The thread pitch for the Ithaca barrel stud is an 8-36. Some Ithaca model 37’s production runs manufactured prior to 1983 did not have the barrel lug drilled or tapped. Most Deerslayer barrels manufactured after 1970 and standard Model 37 manufactured after 1983 were drilled and tapped on the barrel lug.


  1. I have a double barreled shotgun I want to install your GTSW-30 onto. What size do I drill the holes for the screws that come with the adaptor?


The slotted head screws require a hole drilled and tapped for a 4-48 thread pitch.


  1. I recently purchased your GTSW-27 Swivel set. There were a pair of white and a pair of black washers included.  What are those used for?


The washers are a totally optional component of our swivel sets.  You may like the look of a white spacer like the older Marlin 336 with the "White Line Spacer" and classic Remington 700 BDL's, or you may prefer the subtle appearance of the black spacers to provide a smooth transition from the swivel stud to the wood stock.  You may also choose not to use them at all and just have a simple wood to metal fit between the stock and the swivel stud.  The washers are included to give you the option of how you want your firearm to look.


  1. I just bought a Leupold scope for my Winchester 1885 single shot. What hammer extension can I use on it?


The design of the 1885 rifle makes the hammer recede into the receiver when the lever is opened. You cannot use a hammer extension on any 1885 rifle.


  1. I have an early 1955 Marlin 336 lever action rifle with a scope on it. Do you make a hammer extension for these early Marlins?


No.  The Marlin 336 has three distinct hammer styles by production dates: 1948 thru 1956, 1857 thru 1982, and 1983 to present with the introduction of the cross bolt safety.  GrovTec only manufactures hammer extensions for the 1957 to 1982 models with the GTHM-70 and for the 1983 to present models with our GTHM-74.