The More You Know: Length Of Pull

Credit: Magpul

Credit: Magpul

Like a lot of technical terms in the firearms world, the ‘length of pull’ measurement is used often, but may not always be properly understood. And while the concept itself is pretty simple, I decided to consult an expert for a full explanation. Luckily for me, I already had the right guy to call in my address book.

Steve Rose is the owner/operator of Rose Action Sports in Pembroke, Kentucky. Rose is a master gunsmith who upgrades and repairs a broad spectrum of firearms for sport and competition shooters across the country. I first met Steve a few years ago when he cut a barrel, threaded it for chokes and set the front sight for a Remington 870 Short Barreled Shotgun (SBS) build I nicknamed “The Woodsman”. Steve’s craftsmanship and customer service are top-notch.

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Ironically, “The Woodsman” has an especially short LOP.

Steve, what is ‘Length of Pull’?

Length of Pull (LOP) on the shotgun or rifle is the distance from the trigger to the back center of the butt plate or recoil pad. LOP is one of the primary measurements in determining if the gun “fits” the shooter.

Why is a proper LOP so important?

Whether it be for hunting or competition use, a properly LOP fitted gun allows the shooter to shoulder the firearm comfortably, puts the head and eye into position for a consistent sight picture, and allows for the most efficient gun movement (“swing”) while the gun is held up in the firing position.

When the LOP is too long the gun will be difficult to mount as the stock will drag under the shooter’s arm as it is raised into position, the gun will pushed out in front of the shooter making movement (ie “swinging the gun”) more unnatural and uncomfortable. A LOP that is too long will also make a consistent sight picture difficult to achieve as the shooter’s eye and head position is too far back from the rifle scope or shotgun receiver. A LOP that is too short allows the support hand to contact the shooter’s nose or face under recoil or, in the case of a scoped rifle, the shooter’s eye may get too close to the scope leaving a “Weaver eyebrow” from a heavy recoiling gun.

Is there a proper way to meaure LOP?

A general rule of thumb when testing a gun’s fit is that the thumb of the support hand (the hand around the wrist of the stock) should be about 1.5” from the shooters nose when the firearm is shouldered just like you are shooting it. (The old wives tale about holding the gun stock in the crook of the arm is just that, an old wives tale, and does not really tell us if the LOP matches the shooter).

We often test fit guns to the shooter by taping on temporary cardboard spacers to simulate a longer LOP or removing the factory recoil pad and/or trimming the stock length to achieve a shorter LOP. After the correct length is determined the stock can be lengthened with a thicker recoil pad and/or spacers. Slip over recoil pads that the shooter can install themselves are also available. A shortened stock will be trimmed to final length and new recoil pate or butt plate installed. In some cases the factory pad might be reused.

Is there such a thing as a one-size-fits-all LOP?

Over the years each manufacturer has determined what they consider the typical, average LOP for their customer – but much like going into a clothing store and finding every T shirt is size LARGE you take your chances with getting a good fit if you vary much from that “average size” category. Buying a firearm without the opportunity to handle and shoulder it does leave a little to chance so if at all possible try to handle a similar model at a store, range, or from a fellow shooter. Luckily some firearms are now designed with multiple stock spacers or recoil pads included to allow the owners to achieve a more personalized fit and if not, your local gunsmith is likely well equipped to fit your new shotgun or rifle to you.

Thanks Steve.

And that’s, The More You Know.

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Rose Action Sports – http://www.roseactionsports.com/
1200 Beeker Rd
Pembroke, KY 42266

Please call for an appointment. We are available 8-5 M-F and 8-Noon on Saturday

Phone: 270-348-3262
Email: gunsmith@roseactionsports.com
Rose Action Sports on Facebook



Pete

LE – Science – OSINT.
On a mission to make all of my guns as quiet as possible.
Pete.M@staff.thefirearmblog.com


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  • Joe

    How about with a detached pistol grip rifle? Seems “M4 style stock” is the most prevalent answer. And given the extra long LOP on all rifle cartridge bullpups how detrimental is this to the user?

    • Joe

      Sorry, one more thing: Could the grip/trigger assembly on a bullpup be engineered to be adjustable front to back since the stock can’t?

      • Pete – TFB Writer

        Oh, good question. That’s one for Nathniel F. He’s got the design theory background as well as the love for mutant bullpups. 🙂

        • Joe

          Anyone know which is the shortest of the options available? Best I can tell it would be the X95 without the extended buttpad, but info is spotty online about others.

      • BattleshipGrey

        That would be cool if the whole grip and trigger bar was on a sliding rail.

        • Anonymoose

          Probably would increase weight and complexity a lot though.

          • randomswede

            Probably is right, the electronics needed are stupid simple and not necessarily heavy; but “adding parts” definitely tends to be synonymous with weight and complexity.

            In the paintball world, where electronic triggers are more the norm than the exception and have been around since the mid nineties the only real downside is the need for batteries. If you have an electric marker and don’t bring spare batteries it’s not unlike bringing the gun but no spare magazines.

            If we look at the AR-15 and instead of adding parts we replace parts. The entire trigger pack can go, the new trigger can be very light and will actuate a switch very much like what’s making a computer mouse button work. A battery and some basic electronics would take the rest of the space. Lastly a new BCG and probably bolt would be needed so that the firing pin can be made a solenoid.

            This probably can’t be made legally in the US due to the NFA, any self loading electronic trigger weapon can very easily be made full auto. But rate of fire could be easily adjusted, lock times could probably be around 2ms and trigger pull could be silly light and short.

          • Gary Kirk

            I do believe that it’s a definite no go on the electronic triggers, for the very reasons you stated.. However, electronic ignition has been tried, to no real avail.. Even in the muzzleloader world.

        • Giolli Joker

          If you can cope with an electric trigger group, it should be easily doable.

          • BattleshipGrey

            Ewww.

        • Joe

          I don’t think it necessarily need to be that complex.
          Put additional holes in the trigger bar leading backward an inch or two.
          Put pistol grip and a short beavertail on a slide with locking points corresponding to the holes in the trigger bar.

        • iksnilol

          Or just move the grip farther back and use a conventional extending buttplate.

      • 2805662

        There’s a Polish bullpup with adjustable LOP. Just buy an AR.

        • Joe

          Yes, it adjusts from too long to ridiculously too long.

          I bought my first AR in ’97, but thanks for the tip.

          • 2805662

            Having used an AUG for 23 years, I’d still go with an AR. That’s just me, though.

          • Joe

            I shouldered one a few years back, and yeah, it’s loooong.

      • iksnilol

        You could take a bullpup, move the trigger/grip 10 cm back, then add a buttplate that can be extended 10 cm.

  • Limonata

    What is the proper way to measure LOP for a pistol? I have often see articles that state “fit” but never explain it. I have always suspected that there must be a way to measure for pistol as well. I cannot shoot most compact pistols accurately unless I am slow and deliberate however, my full size XDM I am accurate all the time because IMHO, it fits my palm and trigger reach is perfect. But is there a measure that I could use to determine why that is?

    • ostiariusalpha

      Handguns don’t really use the term “length of pull,” the phrase you are looking for is “trigger reach.” Trigger reach is generally measured from the face of the trigger to the point where the web of your hand sits on the back strap of the grip, but the side panel thickness can have a large effect on trigger reach as well.

    • gunsandrockets

      I suspect the measurement you are looking for is circumference. And sadly about the only practical way of finding out that information is direct handling of a product example.

  • YZAS

    The LOP on the Mossie 930 SPX is especially long. I hope i can find a smith that will take it down for me, but it’s a bit of a pain to do, and without shortening the recoil tube and spring, you can only reduce it by about 1.5 inches. I dont want a pistol grip because of the placement of the safety and have seen reliability issues reported with the Urbino stock because of it’s shortened recoil tube and spring. It’s the one drawback of the SPX. So i can relate to the whole ‘too long LOP’ part above.

    • gunsandrockets

      I find the LOP on a very basic Mossberg 500A riotgun too long for me too.

  • Alex

    Frank from SnipersHide goes over LOP as well. He recommends putting your finger on the trigger with your arm bent at 90* and then adjust the stock to match with the fold in the arm and then bring it in an inch.

    • gunsandrockets

      (The old wives tale about holding the gun stock in the crook of the arm is just that, an old wives tale, and does not really tell us if the LOP matches the shooter).

      • Ondřej Turek

        Yet I’ve been taught it by the CZUB former technological director, who teaches at the CZUB gunsmithery school.

        Hence, I believe that whether this technique is of any use or not is one of those never settled cases where half of tom notch gunsmiths will tell you one thing and the other half the exact opposite.

        I can say the 90°-elbow technique works for me and at the minimum a few of my friends when trying with AR-15’s collapsible stock.

        • Machinegunnertim

          That technique has also worked very well for me. How can it be an “old wives tale” if it works?

  • Harry’s Holsters

    Great Article! I learned a lot I didn’t know before.

  • Christian Hedegaard-Schou

    Many rifles, and especially Remington 870 shotguns ship with a really ridiculously long LOP.

    I want to believe that it’s so people can cut them down and install a nice pad to get the proper LOP for themselves, but we all know people will never do that.

    Then I see lots of people talk about needing these really crazy LOP’s because they’re “tall” or a “big guy”, even though that’s meaningless.

    I used to cringe every time I would see someone pick up an AR and immediately take that collapsible stock allllll the way out to the last setting without even thinking about it.

    • Bob

      Some of us really do have a ridiculous wingspan and find that longest stocks best…

      • Christian Hedegaard-Schou

        No doubt.

        But the majority out there use ridiculous LOP’s not because they need them, but because they THINK they need them.

        • Bob

          I didn’t think I needed a long LOP either, but I put an extension on my Mosin Nagant (a notoriously short stocked rifle if ya didn’t know) and as soon as I shouldered it, the concept of LOP became clear to me.

          • Marcus D.

            I built a Traditions kit Kentucky long rifle. It has a ridiculously short LOP, around 12.5″, and that made the concept clear to me. And yes, I am one of those guys who puts the stock on an AR out at the longest setting–and even then it seems short.

    • BrandonAKsALot

      That used to be me. Then I realized how comfortable AK’s were for me compared to my AR’s and learned the error of my ways. I’m above average height with decent length arms, but shorter LOP feels so much better to me. I keep my AR stocks on the 3rd setting out usually.

      • Bob

        My AK LOP is good as far as my arms and whatnot actually, but I need a longer one to get proper eye relief on the scope, which is mounted as far forward as it can be on the side mount. Gonna switch to a red dot I think. #AKproblems

        • TRAK

          Not AK problems. Just get a Russian scope

  • Gary Kirk

    Like the “woodsman” to a degree, is that ceracoated? Or actually browned metal? Either way, looks good brother.. Different, there is no other way to be..

  • Cmex

    A lot of historical rifles had 13″ LOP, including the Mosin, Garand, SMLE, M1903, G98, AK-47, and even the M16a1, IIRC.

  • Marcus D.

    My son was lucky in this department. I bought a used Wingmaster with some funky adjustable end plate, and one day we went to shoot clays, and there was a smith there who specialized in gun fitting. He removed the funky pieces, measured the fit for my son, and modified the stock right then and there in his trailer.

  • Marcus D.

    It seems to me that a very simple device could be built out of wood or metal with an adjustable sliding “stock” with a built in measuring stick with 0 at the butt end and a window over the “trigger” to show length. You could also mount a block as to where the nose would fall along the top. The buyer would mount the tool, and then with the guidance of the smith, adjust the length to find the right LOP for that particular shooter. Then any rifle or shotgun could be modified as needed.

  • Why no discussion about adjustable triggers?

  • kcshooter

    I have had Rose Action Sports work on 2 of my shotguns and 1 of my rifles, and their work is impeccable. Absolutely top notch. Fast, easy to work with, flawless results. Steve will have another one of my uppers to work on by the end of the summer.

  • gunsandrockets

  • gunsandrockets