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I'm considering purchasing some spare parts for my SP 101.Before I go hog wild and spend money on parts that probably will never be used,I thought I would get some input from the Forum.For all you SP 101 owners and gunsmiths: Has any part wore out or broke on your SP101? Is there any particular part that tends to wear out and cause a stoppage in the normal function of the SP? Any particular spring or plunger,there's a bunch of these,that tend to wear out or launch themselves into oblivion when you're not careful in dissasembly? LOL,You guys know what I mean,we can't help tinkering with something that isn't broke! Any input would be appreciated.Thanks.
 

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I'm considering purchasing some spare parts for my SP 101.Before I go hog wild and spend money on parts that probably will never be used,I thought I would get some input from the Forum.For all you SP 101 owners and gunsmiths: Has any part wore out or broke on your SP101? Is there any particular part that tends to wear out and cause a stoppage in the normal function of the SP? Any particular spring or plunger,there's a bunch of these,that tend to wear out or launch themselves into oblivion when you're not careful in dissasembly? LOL,You guys know what I mean,we can't help tinkering with something that isn't broke! Any input would be appreciated.Thanks.
I completely disassembled mine for polishing and there isn't a single part that I feel would wear out in a lifetime except perhaps the transfer bar. They have been known to break.
 

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The SP101 I've ordered is coming with a hammer. If, at some point, I want to try going hammerless (DAO), can a hammer be ordered? Is this something I could swap out myself?
 

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Crestliner, There's no such thing as hammerless in a SP-101. I think what you mean is spurless. Nope, Ruger won't sell you a hammer but you may be able to find a used one from Gun Parts Inc see: http://www.gunpartscorp.com/
 

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The SP101, also known as the bank safe, and the tank, ever having a wore out or broken part!!!!!!!!!!!!!!!!!!!!!! That's the Ruger Sp101 vault having a break down? This should be in the punchline section. The Superman of concealed carry guns laughs at others worn parts and the carnage of breakdowns.

(If you do know of a problem, don't let me know about it, I still need my heroes. LOL)
 

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Thanks Iowegan! And for stoble - I HEAR YA! :D
 

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The SP101 I've ordered is coming with a hammer. If, at some point, I want to try going hammerless (DAO), can a hammer be ordered? Is this something I could swap out myself?
For about $40 your local gunsmith can just lop that pesky spur right off. Then unlike the DAO spurless version you'll still have a SA cocking notch which you can use safely by:
1 - putting your off hand thumb behind the top of the hammer
2 - pulling gently on the trigger until your offhand index finger can slip in front of the hammer ( you will now be holding the top of the hammer stump between your index finger and thumb)
3 - taking your finger off the trigger
4 - pushing the hammer into the cocked position with your index finger.

The more you shoot the SP101 in DA the less you'll even want to bother with SA. Until you get out to 25 yards the difference in DA vs. SA groups should be so close as to be meaningless for defensive purposes. If not you need more practice :)

Cheers,
Wuchak
 

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I need more practice. If i could shoot it a well as I shoot my Sig 229 I would be extremly happy. Its not the 101's fault It's me anticipating the recoil and flinching, so I need alot of practice. Cant wait to stat practicing, thats the fun part.
 

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I like the option of that spur, fer semi-precise shooting at paper, and cans, but fer the intended role of my SP, I'm thinking about reducing the length of the spur, about an eighth of an inch or so. Just a little less protrusion, and I won't lose much mass. 'Damn transfer bar requires more impact, by sustained impetus of the hammers' mass, or by forward speed, from the weight of the mainspring; to achieve proper firing-pin smack, when compared to 'hammer noses' and such.
 

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Don b.

I have not heard otherwise, so I'd assume the DA only SP101 uses the same mainspring as the regular SP101. That bobbed hammer has to weigh a good bit less than the regular hammer. Since e = 1/2mv^2, the lighter hammer hits hard enough to set off the primer because it's moving faster. Less lock time too. Velocity has a much bigger role there than does weight.

So if you were to lighten your current hammer by grinding off the spur, or by drilling a few strategic holes in it in safe places, or by contouring it to match the curve of the frame, then it would accelerate faster and hit harder with any given spring, compared to the stock hammer. A slightly lighter hammer will always hit harder.

I'm sure there's some expensive gizmo somewhere that can measure exactly how hard any hammer hits and how fast it's moving, and probably some way to test how hard a hit is necessary to set off any particular primer. Otherwise it's trial and error. But there is probably a minimum combination of hammer mass and spring strength that gets the job done against the toughest primer, with each of the available springs.


What I'd like is a photograph, or a drawing, that shows me where I can safely drill to lighten my hammer. Contour matching will save me a few grams, but not much more than that.
 

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Don't mean to be obnoxious, but I've seen several times here the idea that since hammer energy is given by 1/2 M V^2, ANY decrease in hammer weight will increase speed and thus energy, (regardless of WHERE the metal is taken from).

Not quite. As Iowegan has pointed out, one should decrease hammer mass - if THAT is the thing you are trying to do - by taking metal out of the hammer BELOW its end. One fellow took issue with this (can't find the post now), and declared that it did not matter WHERE you took out the metal, since "E=1/2 M V^2, and 'the mass is the mass'.

Wrong. What is forgotten here is that the velocity we are dealing with is the velocity of the CENTER OF MASS of the hammer. This is because the hammer is NOT a 'free body', but is rotating around its pivot pin!!! If the rotating body is a uniformly thick piece, then the center of mass is halfway from the pivot to the end. But . . . the hammer is decidedly NOT a uniformly 'thick' piece!

The velocity of a part, "p", of a rotating body is given by the radius, (distance from the pivot to that part), times the angular velocity of the piece; "W" (W = Omega; have no greek letters on this keyboard.....), and is thus Vp= RW. THIS is the velocity that must be used in the energy forumula, where Vp is the velocity of the center of mass.

So... if we reduce the weight of the hammer STRUT, we effectively move the CENTER OF MASS up towards the end (striking part) of the hammer. This increases "R" in the above, thus increasing Vp. Since Vp is SQUARED in the energy calculation, a small increase in Vp, by a small increase in R, gives a much larger increase in the energy of the hammer.
Example: if the effective "R" is say 0.5" originally, and we can increase it to say 0.7" by taking mass off the strut, we have made a 40% increase in "R", (and a similar increase in Vp). Since 1.4 is nearly the square root of 2, we have essentially DOUBLED the energy of the hammer (disregarding for the moment the decrease in overall mass). This even assumes that the angular velocity is the SAME! But it will not be, as the hammer is lighter! So - as Iowegan clearly said - you get a double improvement by taking mass from below the hammer's 'end'!

Bottom line: if you take mass from the END of the hammer, i.e. by grinding off the 'spur', you move the CENTER of mass of the whole hammer DOWN - closer to the pivot - and DECREASE "R", and thus "Vp". So though the rotational velocity of the hammer will surely increase, you may well LOSE effective energy of this rotating part.

I know many folks 'de-spur' their hammers, and I've always wondered if this has caused any 'light strikes', or if they also put heavier springs in too. . . .??

If I'm wrong about this, any of you experts please correct me. {:)
 

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shoot44, Though a bit complex, I think you nailed it. Ruger DAs hammers are way over sprung from the factory. You can bob a hammer (which indeed does reduce firing pin energy) and still have enough energy for solid primer hits. Now if you use a reduced power hammer spring with a bobbed hammer, you may experience misfires, especially with harder magnum primers.
 

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I need more practice. If i could shoot it a well as I shoot my Sig 229 I would be extremly happy. Its not the 101's fault It's me anticipating the recoil and flinching, so I need alot of practice. Cant wait to stat practicing, thats the fun part.
Do you mean for accurracy or for speed. It is going to be very tough to duplicate or beat double taps from your Sig 229. I have a 101 and a Glock 19. I have no dreams of being able to shoot my 2 in. 101 as good or better as I do with the 19. The semi auto has too many advantages.
 

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a glock 19 and sp101 are two totally different types of guns and you can't compare them in the same category. With proper practice and getting used to the sp101 it is a very accurate gun when used for what it is designed for.
 
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