Sentinel Machineshop's Centroid CNC Acorn conversion of a WMTCNC ZAY7025VB Benchtop milling machine. Home CNC is now at your fingertips!

Centroid CNC Conversion of PM-25 clone ZAY7025VB

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Sentinel’s Best Mini Mill comparison

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Best LED Shop Lights

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Atlas Lathe awesome upgrade – treadmill motor conversion

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Chapman 9600 Gun screw driver kit

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Best Torque Wrenches for Gunsmithing- Top 10 Reviews

Torque wrenches for Gunsmithing.

As with all things, all Torque wrenches are not created equal so we compiled a list of Best Torque Wrenches for Gunsmithing. As we all know you will read on the internet all sorts of boastful claims that cannot be backed up by reality. In this article we discuss which tool is best for the intended purpose and why. Let’s get started, we went through the inch pound (in/lbs) torque wrenches listed on everybody’s favorite go to, and ranked the top 10 in both the under 65 in/lbs category and the under 250 in/lbs category.

The following is the top ten list for the under 65 in/lb category. The best torque driver for gunsmithing in this category is a tight race between the top three, the winner is the CDI 401SM with a range from 5-40 in/lbs with adjustments every .5 in/lb with an industry standard ±6% accuracy that can be backed up by years of industrial use in this country not a certificate that may or may not be worth the paper it is written on. CDI is a Snap-on company and the quality and precise repeatability of this tool shows and it is made in the USA.

The range of the top two on the list are best suited to the driver torque wrench, covering your smallest fasteners giving you the most accurate and repeatable torque. They are great for scope base install, trigger adjustment locknuts, ring caps, stock side retaining screws etc. With that said, the top half of entries on this list are all tools that would be used professionally in a situation where accuracy matters. That’s why we use a torque wrench, for accuracy and consistent repeatability, not just close enough and not stripped or broken.

Top 10 0-65 inch pound torque drivers

1CDI /Snap-on401SM5-40± 6%.5 In/lbsNONE1 YearUSA
Precision InstrumentsPREMD1F35H5-35± 6%.5 In/lbsNONE1 YearUSA
3ProtoJ6106ACERT7-36± 2%1 In/lbsNONE1 YearUSA
4Wera507471100129-Nov± 6%1 In/lbsNONE1 YearCZ
5WiHa2850610-50± 6%2 In/lbsNONE1 YearGermany
6WiHa2860010-50± 6%2 In/lbs181 YearGermany
7Teng Tools1492USD10-50± 4%1 In/lbsNONELifetimeTaiwan
8CapriCP2107510-50± 6%1 In/lbs20NoneChina
9First InfoH518810-90± 6%2 In/lbsNONE1 YearChina
10WheelerFAT wrench15-100No standard5 in/lbs10NoneChina


#1           CDI /Snap-on      401SM

Torque wrenches for Gunsmithing

The CDI 401SM Micro Adjustable Torque Screwdriver from Snap-On Industrial Brands has a 1/4″ Female Hex Drive and English range of 5-40 In Lbs . Adjustable models offer versatility for applications that require more than one torque value. These hex torque screwdrivers are particularly suited for the firearms and gunsmithing industry.

A simple, cam-over design prevents over-tightening and possible damage to components. Torque settings are easily and accurately changed with a unique adjusting knob and easy-to-read window scale. Adjusting the screwdriver is simple. Just pull out the adjusting knob to unlock, turn to the desired setting, then push the knob in until it clicks! Positive locking knob makes accidental setting changes impossible. This 1/4 drive torque screwdriver features an automatic lock in the counterclockwise direction to make fastener removal a snap.

Meets or exceeds ASME B107.14 – 2004



#2           Precision Instruments      PREMD1F35H

Torque wrenches for Gunsmithing

As hand drivers are more convenient than ratchet wrenches for some applications, torque drivers are more convenient than torque wrenches for some applications. Delicate applications such as scope ring screw and fasteners used in plastics are examples of low-torque applications where tolerance is extremely tight and a torque driver is ideally suited. Also, torque drivers are not hand-hold sensitive.

The guaranteed accuracy of this torque screwdriver exceeds the requirements of: MIL-W-26497C



#3           Proto      J6106ACERT

Torque wrenches for Gunsmithing

The Proto J6106ACERT Adjustable Torque Screwdriver has a 1/4″ Drive and an English range of 7-36 in-lbs Manufactured to meet standard industrial torque applications such as general industry, heavy equipment and maintenance.

Meets or exceeds ASME B107.14M – 2004



The next category is the top ten list for the under 250 in/lb category. The best torque wrench for gunsmithing in this category is also a toss up between the top 3 and personal preference. The top two are a dial type wrench that are extremely accurate but require you to be able to see the dial from straight on. The third wrench on the list I own and is a click type micrometer style torque wrench with 1 in/lb graduations. All three choices are made in the USA and you cannot go wrong with either one of them.

These wrenches are great covering the larger items like stock to receiver screw, ring/scope mount to base fasteners, adjustable butt fasteners etc.

Top 10 under 200 inch pound Torque wrenches

1Precision InstrumentsPRED2F150HM0-150± 2%Dial3/8" male1-YearUSANone
2CDI1502LDIN0-150± 3%Dial3/8" male1-YearUSANone
3CDI /Snap-onCDI1501MRMH20-150± 3%1 In/lbs1/4" male1-YearUSA24
4Capri3120020-150± 4%1 In/lbs1/4" male1-YearTaiwan64
5GEARWRENCH8506030-200± 3%1 In/lbs1/4" maleNoneChina22
6Bull ToolsFLD-wq003-420-200± 3%2 In/lbs1/4" maleNoneChina72
7YoleoBike Torque Wrench9-221± 4%2 In/lbs1/4" male15-MonthTaiwan72
8Capri3100720-245± 4%1 In/lbs1/4" male1-YearTaiwan24
9TEKTON2432020-200± 4%2 In/lbs1/4" maleNoneChina24
10TEKTONTRQ2110110-150± 4%1 In/lbs1/4" maleNoneChina72


#1            Precision Instruments      PRED2F150HM

Torque wrenches for Gunsmithing

The Dial Type Wrench provides an excellent solution for many applications. The wide range of scales makes selecting the appropriate tool easy. Accurate to 2% of the reading from 20% of full scale to full scale clockwise and counterclockwise, the Dial Type Wrench is the most accurate torque wrench family. The Dial Type Wrench is the only wrench that is not affected by the hand-hold position on the wrench. I used this torque wrench to install to install the SPUHR ISMS in the review article.

Meets or Exceeds the following Specifications: GGG-W-686C, ANSI B107.14M

#2            CDI      1502LDIN

Torque wrenches for riflesDial Torque Wrenches are designed for the automotive, nuclear and industrial markets in addition to military installations throughout the world. This series features sturdy torsion beam design for dependable long life and accuracy. The small frame model offers working ranges from 3 in. lbs. to 50 ft. lbs. in 1/4″ and 3/8″ drives. The large frame model continues from 100 ft. lbs. through 2,000 ft. lbs. with 1/2″, 3/4″ and 1″ drives. Accuracy of both series of ± 3% meets or exceeds ASME standards, ISO 6789 bi-directionally from 20% to 100% of scale.

All wrenches supplied with a N.I.S.T. traceable certificate of calibration.The CDI 1502LDIN is CDI’s Dial Torque Wrench, offered by Pro Torque Tools.  The CDI 1502LDIN has a 3/8″ drive and a dual scale, as well as an English range from 0 to 150 in lbs and a metric range from 0 to 18 Nm. Meets or exceeds ASME B107.14 1994, ISO 6789

#3            CDI /Snap-on      CDI1501MRMH

Torque wrenches for Gunsmithing

Metal Handle Dual Scale. The metal handle series offers the user a rugged, industrial strength torque wrench able to withstand the rigors of professional use. Handles are lightly knurled for a tough, non-slip grip Individually serialized with matching certificate of calibration traceable to N.I.S.T.

Meets or exceeds ASME B107.14-2004, ISO 6789 standards

USMC MST-100 & MST-100M Glass etched reticle retrofit

Available only through Sentinel Tactical is a glass etched reticle retrofit for the USMC UNERTL MST-100 & MST-100M. If you own a USMC MST-100 from an M40a1 or the Canadian C3A1 MST-100M scope you will understand why the glass etched reticle is a great idea. All of these old scopes are just waiting for the …