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-   -   1903 Springfield Trigger Improvement (http://forums.thecmp.org/showthread.php?t=83747)

sigman2 08-22-2012 12:51 AM

1903 Springfield Trigger Improvement
 
Moderator, you may want to make this a sticky.

The following is for the M1903 Springfield Rifle but will be the same for any Mauser type rifle.

I have removed text that was not pertinent to the scope of this post.



WAR DEPARTMENT TECHNICAL MANUAL
TM 9-1270

ORDNANCE MAINTENANCE

U.S. Rifles, Cal. .30, M1903, M1903A1, M1903A3 and M1903A4
20 January 1944




28 Rifle As A Unit.

c. Trigger Pull

(1) Trigger pull for rifles in service must be greater than 3 pounds but should not exceed 6 pounds.

(4) “Creep” is any movement of the trigger that can be felt by the finger after the slack has been taken up and before enough pressure is applied to release the sear. Creep should be eliminated as much as possible, whenever found, as it prevents the proper squeeze of the trigger, which is essential to the proper firing of the rifle.



47 Receiver Group.

f. Trigger

(1) Burrs on bearing and heel of trigger should be removed with a sharpening stone, care being taken not to remove too much metal. A loose trigger pin, especially if it allows side play, should be replaced.

(2) When creep, as defined in paragraph 28 c (4), is found in a trigger, or when the trigger pull does not fall within the prescribed limits, examine the sear nose and sear notch for burrs or rough surfaces. All burrs should be removed by stoning and all surfaces which are not perfectly smooth should be polished by stoning. Sharp corners and edges should not be rounded off. Should this procedure fail to produce the desired degree of smoothness in the action or the desired correction in trigger weight, the heel of the trigger and the point at which it comes in contact with the receiver should be inspected and any roughness removed by stoning. Should the action still be faulty, it will be necessary to interchange the parts until a combination of cocking piece, sear and sear spring, trigger, and mainspring is found which will correct the difficulty. The probable importance of these various parts in the perfection of the trigger pull is in the order given. A number of parts should be tried in their various combinations until a satisfactory pull is obtained. The shapes of the coking piece sear notch and sear nose and the strength of the sear spring should always be such that the sear invariably rises to its full height and the trigger returns to its forward position on a cocked rifle when the trigger is released.

tjtorborg 08-22-2012 09:04 AM

This is great information. I have been looking for something to tell or show me how to smooth out my springfield triggers for a long time. I wish someone had pictures of how to do it like the ones for the Garand trigger jobs you see from time to time.

Thanks,

Tom

GGaskill 08-23-2012 07:52 PM

The following is also in the Ask Each Other forum but does not have the pix:

There are two other things you can do for a better and lighter trigger pull. One is switch springs until you get one that will reset the first stage when you let go of it but little more. That reset is a safety factor so do not use a spring that will not reset properly. If you want to use the rifle in CMP as-issued matches, the rules require that the trigger lift a minimum of 3.5 pounds.

The other thing you can do requires modification of the sear beyond smoothing surfaces. The goal is to reduce the engagement of the second stage to a minimum so that only a little additional motion into the second stage releases the firing pin. This can be done using a medium India stone and lots of reassembly and testing. It can be overdone such that you will need to buy a new sear but they are readily available and not very expensive. When I did this on some of my rifles, I bought extra sears first and did the modifications on them, so I had the originals as backups.


http://www.gunneyg.info/images/searmod1.jpg

The stone is a Brownells' (actually a Norton, I think) 1/2 square x 6 medium India stone. Use some light oil to prevent the swarf from filling up the stone. Put most of the pressure over the sear end; you will take a little off over the pin holes but not enough to matter. You will need to trial fit the sear frequently or you will go too far. Don't make it unsafe; if you blow the first one, buy a replacement and try again.

http://www.gunneyg.info/images/searb4aft.jpg

Before and after. Actually the after went too far but it shows the results of the process. The sear top is wider because it is lower down the angle.

On an M1917, you have to stone the sear sort of diagonally because of the spring guide. Same basic idea, though.

TW56 08-25-2012 11:34 AM

If you have extra cocking rod assemblies, you can sometimes get rid of creep by switching the cocking rod and leaving the sear and trigger alone.

Great USGI information on what to do however.

TW56

tjtorborg 08-25-2012 06:07 PM

Would this modification be allowed in a "as-issued" CMP rifle match? Or would this DQ the rifle?

Thanks,

Tom

TW56 08-25-2012 10:33 PM

Tom, an e-mail to Mark Johnson asking for a ruling regarding stoning a sear or trigger.

TW56

Allen Humphrey 08-29-2012 09:48 AM

It seems to me that so long as a)USGI parts are used b) function is not altered (think of stoning until the first stage is gone) c)trigger pull meets or exceeds the stated minimum and d) no other parts like shims or screws are added then the rifle would meet the requirements of 6.3.1. The documet in the OP shows that the military understood that the manufacturing tolerances of the parts involved could produce noticably different results at the trigger and encouraged the careful assembly of parts and smoothing to get the desired feel.

My experience at the Western Games in 2011 was pretty straight forward. The guy grabbed my rifle and looked at it just long enough to determine that it wasn't an M1, lifted the weight, put a sticker on it, and handed it back to me. I'd guess that an in-depth inspection would still only visually confirm that a USGI design trigger group was in place. just my 2 cents.

tjtorborg 08-29-2012 10:18 AM

Allen,

I agree and that has been my experience the last 9 years at Camp Perry as well. I just sent an email to Mark Johnson asking is it okay to stone a trigger and/or sear to improve trigger pull. I post his answere here as soon as I get it.

Thanks,

Tom

tjtorborg 08-29-2012 11:00 AM

Hey guys,

Here is the response from Mark Johnson about my email concerning stoning to improve trigger pull:

"No problem as long as the trigger pull will make weight and still has a defined two stages."

Pretty clear and super fast response time!

Tom

Allen Humphrey 08-29-2012 12:19 PM

Cool. To me that confirms that the Vintage "Games" are intended to be fun events and that the rules set the spirit of the format without needing to get burried in the minutia of microscopic inspections. Real cheaters will be discovered and shunned. Probably no amount of cheating would make that person shoot well enough to win anyway as the good shooters I know don't need to cheat to beat anybody:)

Its nice that Mr. Johnson was able to answer you so quickly.


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