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GrovTec US Henry Big Boy Hammer Extensions Up to 38% Off — 13 models

GrovTec US Hammer Extension Spur, Marlin Model 36 - 1936-1947 and Marlin Model 336 - 1948-1956, Black, GTHM308
GrovTec US Hammer Extension Spur, Winchester 94s and Big Bore 94s, Ithaca X-Caliber, Black, GTHM68
GrovTec US Hammer Extension Spur, Marlin Lever Actions 1957-1982, Black, GTHM70
GrovTec US Hammer Extension Spur, Browning BLR 1981-1991, Will Not Fit 1992 And Later Models, Black, GTHM73
GrovTec US Hammer Extension Spur, Henry Big Boy, Older Pre 2010 Centerfire Rifles, Black, GTHM277
GrovTec US Hammer Extension Spur, Browning BLR 92, Black, GTHM285
GrovTec US Hammer Extension Spur, Browning BL-22, Astra 357, Black, GTHM71
GrovTec US Hammer Extension Spur, Marlin Model 36 - 1936-1947 and Marlin Model 336 - 1948-1956, Black, GTHM308
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GrovTec US Hammer Extension Spur, Marlin Model 36 - 1936-1947 and Marlin Model 336 - 1948-1956, Black, GTHM308
GrovTec US Hammer Extension Spur, Winchester 94s and Big Bore 94s, Ithaca X-Caliber, Black, GTHM68
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GrovTec US Hammer Extension Spur, Winchester 94s and Big Bore 94s, Ithaca X-Caliber, Black, GTHM68
GrovTec US Hammer Extension Spur, Marlin Lever Actions 1957-1982, Black, GTHM70
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GrovTec US Hammer Extension Spur, Marlin Lever Actions 1957-1982, Black, GTHM70
GrovTec US Hammer Extension Spur, Browning BLR 1981-1991, Will Not Fit 1992 And Later Models, Black, GTHM73
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GrovTec US Hammer Extension Spur, Browning BLR 1981-1991, Will Not Fit 1992 And Later Models, Black, GTHM73
GrovTec US Hammer Extension Spur, Henry Big Boy, Older Pre 2010 Centerfire Rifles, Black, GTHM277
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GrovTec US Hammer Extension Spur, Henry Big Boy, Older Pre 2010 Centerfire Rifles, Black, GTHM277
GrovTec US Hammer Extension Spur, Browning BLR 92, Black, GTHM285
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GrovTec US Hammer Extension Spur, Browning BLR 92, Black, GTHM285
GrovTec US Hammer Extension Spur, Browning BL-22, Astra 357, Black, GTHM71
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GrovTec US Hammer Extension Spur, Browning BL-22, Astra 357, Black, GTHM71

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Questions & Answers
Which model do I need for a Henry 45-70 side gate? Expert Answer

The GrovTec US Hammer Extensions for the Henry Big Boy will work for the Henry 45-70 Side Gate.

by Hunter, Gear Expert, March 27, 2023
Would any of your hammer extensions fit a Winchester 62A pump? If it has a too large of an opening, I could fill it in w/ epoxy so that it fits. Expert Answer

There is not a specific model GrovTec US Hammer Extension for the Winchester 62A.

by Hunter, Gear Expert, May 23, 2023
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Customer Reviews
Helpful Positive Review
Fits Henry 45-70 by dwingit, Verified Owner, February 17, 2018
This hammer extension fit my Henry 45-70 perfectly. It makes the use of a scope on a lever action easier to access the hammer without having to worry about fumbling for it under the scope. It made shooting my rifle a much smoother process.
1/1 found this helpful
Helpful Negative Review
Could have been mispackaged, but not the right product by Drew, Verified Owner, December 22, 2016
Got this GTHM-284 model which is supposed to be for Henry lever action Rimfires. Was for a Henry youth model lever action .22lr. Packaging of the product is correct, but the space where the hammer fits is a good 1.5 times too wide. Like something ...
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1/1 found this helpful
Most Recent Reviews
Henry .22 Hammer Extension by JP, Verified Owner, July 21, 2024
I use the hammer extension on a H001 Henry .22 lever action. It makes it possible to work the hammer when a scope is installed on the rifle, making operation much safer if decocking on a loaded chamber. The only issue I have is that the back of the b...
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Most Recent Reviews
Hammer Extension by Robert, Verified Owner, April 3, 2024
The extension fitment is good and seems to be well built. It provided the additional scope clearance needed for hammer cocking and de-cocking.
Most Recent Reviews
Comfortable and tough. by gene, Verified Owner, October 27, 2023
If you own a lever action rifle or a hunting revolver you know the pain of manually pulling back the hammer... These GrovTec US Henry Big Boy Hammer Extensions will come to the rescue every time... They are NOT flimsy plastic, instead they are rugged...
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Most Recent Reviews
Works great, after I filed the groove to fit by Cruz, June 9, 2023
Didn't fit on my 45-70 Henry All Weather Picatinny. Had to file the side of the opening opposite the set screw. The channel at the bottom cleared the underside of the hammer, but the main groove was too narrow to clear the textured top of the hammer....
Read More...
Read All 12 Reviews
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13 Models Available
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Product Info for GrovTec US Henry Big Boy Hammer Extensions

Different hammer extensions to fit your firearm with an exposed hammer after you mount a scope.image

WARNING: California`s Proposition 65

Specifications for GrovTec US Henry Big Boy Hammer Extensions:

Manufacturer: GrovTec US
Color: Black
Fabric/Material: Steel
Condition: New

Package Contents:

  • GrovTec US Henry Big Boy Hammer Extensions

What firearm models does the manufacturer say GrovTec US Henry Big Boy Hammer Extensions is compatible with?

The manufacturer says that GrovTec US Henry Big Boy Hammer Extensions is compatible with Marlin Model 36, Marlin Model 336, Marlin Model 375, Marlin Model 62, Marlin Model 57, Marlin Model 57M, Marlin Model 444, Smith & Wesson Model 29 N-Frame Revolver, Thompson/Center Contender, Marlin Glenfield Model 30A, Marlin Model 1984C, Marlin Model 1895S, Marlin Model 444S, Winchester Model 1894, Marlin Model Golden 39A, Henry Single Shot, Winchester Model 1894 Angle Eject, Winchester Model 1894 Big Bore, Ithaca X-Caliber, Henry Big Boy

GrovTec US Henry Big Boy Hammer Extensions Orderable Models

List of Orderable Models

  • GrovTec US Henry 22 Pump & Lever Action Hammer Extensions, Black, GTHM284 , MPN: GTHM284 , UPC: 811071012843 , Code: 8Z-HMS-GTHMREX2-GTHM284
  • GrovTec US Marlin Lever Actions 1983/Glenfield 30A Hammer Extensions, Black, GTHM74 , MPN: GTHM74 , UPC: 895474001741 , Code: 8Z-HMS-GTHMREX2-GTHM74
  • GrovTec US Model Marlin 36/336 Hammer Extensions, Black, GTHM308 , MPN: GTHM308 , UPC: 811071013161 , Code: 8Z-HMS-GTHMREX2-GTHM308
  • GrovTec US Winchester 94s/Big Bore 94s w/Angle-Eject/Ithaca X-Caliber Hammer Extensions, Black, GTHM68 , MPN: GTHM68 , UPC: 895474001680 , Code: 8Z-HMS-GTHMREX2-GTHM68
  • GrovTec US T/C Contender/S&W Model 29 Hammer Extensions, Black, GTHM79 , MPN: GTHM79 , UPC: 895474001796 , Code: 8Z-HMS-GTHMREX2-GTHM79
  • GrovTec US Marlin Lever Actions 1957-1982 Hammer Extensions, Black, GTHM70 , MPN: GTHM70 , UPC: 895474001703 , Code: 8Z-HMS-GTHMREX2-GTHM70
  • GrovTec US Winchester 94/22 Hammer Extensions, Black, GTHM69 , MPN: GTHM69 , UPC: 895474001697 , Code: 8Z-HMS-GTHMREX2-GTHM69
  • GrovTec US Browning BLR 1981-1991 Hammer Extensions, Black, GTHM73 , MPN: GTHM73 , UPC: 895474001734 , Code: 8Z-HMS-GTHMREX2-GTHM73
  • GrovTec US Henry Big Boy Hammer Extensions, Black, GTHM277 , MPN: GTHM277 , UPC: 811071012775 , Code: 8Z-HMS-GTHMREX2-GTHM277
  • GrovTec US Browning BLR Hammer Extensions, Black, GTHM285 , MPN: GTHM285 , UPC: 811071012850 , Code: 8Z-HMS-GTHMREX2-GTHM285
  • GrovTec US Henry Single Shot Hammer Extensions, Black, GTHM283 , MPN: GTHM283 , UPC: 811071012836 , Code: 8Z-HMS-GTHMREX2-GTHM283
  • GrovTec US Ruger Blackhawk/H&R Topper Hammer Extensions, Black, GTHM72 , MPN: GTHM72 , UPC: 895474001727 , Code: 8Z-HMS-GTHMREX2-GTHM72
  • GrovTec US Browning BL-22/Astra 357 Hammer Extensions, Black, GTHM71 , MPN: GTHM71 , UPC: 895474001710 , Code: 8Z-HMS-GTHMREX2-GTHM71

GrovTec US Henry Big Boy Hammer Extensions Unavailable & Discontinued Models

List of Unorderable Models

  • USED GrovTec US T/C Contender/S&W Model 29 Hammer Extensions, Black, GTHM79, EDEMO1, Condition Parts Only/Salvage, Wrong Product , MPN: GTHM79-EDEMO1 , Code: 8Z-HMS-GTHMREX2-GTHM79-EDEMO-WP-F
  • USED GrovTec US Henry Single Shot Hammer Extensions, Black, GTHM283, EDEMO1, Condition Parts Only/Salvage, Defective , MPN: GTHM283-EDEMO1 , Code: 8Z-HMS-GTHMREX2-GTHM283-EDEMO-DF-F
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