20 LPI checkering greatly improves the grip and helps keep the pistol steady in the hand for improved recoil control. First choice of top combat shooters. Finish-machined from a solid steel casting, no fitting required.
SPECS: Chrome Moly blued or 410 stainless steel, flat or arched. Fits Govt./Commander 2-1/16" (5.2cm) long, .536" (13.6mm) wide.
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Customer ratings for JOHN MASEN FLAT CHROME MOLY
Number of ratings: 12
From brownells.com: 12
Average rating: 1.8
Good for the price(19/02/2012)
Fits my 1911 real good. I prefer an arched ms over a flat ms. Finish isn't excellent thats why I can't give 5 stars. The finish looks dull stainless not a nickel stainless.
Pin hole didn't line up(22/08/2011)
The pin hole did not line up. I had to machine it to get it to fit my Springfield.
not bad for the price(02/07/2014)
I bought this item to replace the plastic mainspring housing on my Rock River 1911 that came with a plastic mainspring housing. I bought it on silver thinking that it would look nice as a two tone part on the gun but it didn't. I then realized the mainspring housing on my Kimber was also plastic so I decided to put it on that gun. It fitted fine with no modifications. It matches the stainless still finish from the Kimber. The only disappointment was the serrations are not sharp enough for my liking. They won't shave layers of skin from you hand like sand paper but I like them a little sharper than what they are. All in all, for the price, it is a good fit.
not cast to advertised specs(11/07/2010)
the manufacturer, (or brownells) states that the MSH is .536 wide. It is, on the underside. The exposed side varies between .517 and .522 and leaves a very large gap between the MSH and the frame. The width at the ribs is .605, about .02 too narrow. Additionally, the checkering is cast very poorly.
quality control is way off on this one.
Great Value(16/04/2013)
I love the feel and the value can't be beat. It did require some fitting to install it on a STI Spartan 9mm (Pin hole needed a little work). The bluing is OK and flat, which matches my gun. I like it.
You get what you pay for.(21/05/2014)
Simply put, the pin hole to secure part into the frame was off 1/16, the part had dings, the finish was all scratched up,& the checkering had no sharpness to it at all. This part may be good for a visual aid only.
Very Poor Quality and Workmanship(13/09/2016)
Despite other poor reviews, I took a chance and ordered this mainspring housing. It just arrived, and I was instantly disappointed with the quality.
First and foremost, the checkering quality is very poor. It is not uniform, and the points are very blunt.
Second, there are tool marks on flat surfaces which will be visible after this mainspring housing is installed.
I am going to return this mainspring housing and purchase a different/better type. This would be a definite downgrade to the appearance of my M1911A1.
DON'T WASTE YOUR MONEY ON THIS PART!!!!!(13/01/2011)
Was doing an upgrade job on a customers 1911 and decided I would try one of these to see how it would work. BAD IDEA!!!!!!!!!! This part is a peice of junk indeed. Did not fit the MS slot to begin with and then the retaining pin hole didn't line up either so I chuncked it in the trash, [$]lesson. Again DON'T WASTE YOUR TIME NOR YOUR MONEY. Get a Wilson and be done with it.
I WONT BE USING THIS PRODUCT AGAIN(13/05/2013)
WHEN I TOOK THIS PRODUCT OUT OF THE BAG AND SLID IT ON THE FRAME I IMMEDIATLY NOTICED THAT THE MAINSPRING HOUSING PIN HOLE DID NOT ALIGN WITH THE HOLES IN THE FRAME. THE HOLE IN THE MAINSPRING HOUSING WAS A GOOD .020 TO .030 MISALIGNED. ALSO THE RAILS THAT SECURE IT TO THE FRAME ARE TOO NARROW AND THE MAINSPRING HOUSING IS VERY SLOPPY IN THE FRAME ALLOWING THE GRIP SAFETY TO HAVE EXCESSIVE TRAVEL UP AND DOWN THAT ALMOST RELEASES THE END OF THE GRIP SAFETY.
WORTHLESS TRASH(15/06/2013)
I ordered this last week to replace to too-large arched mainspring housing on my new (to me) Colt, my first 1911. As other reviewrs have mentioned, the hole for the mainspring housing pin is WAY OFF CENTER and in -2- directions. It is not drilled closely enough to the rail, and even if it were, the MSH would stick out about .10" - .15" from the bottom of the grip frame, interfering with the magwell installation. My fault- I was directed to this part by a Brownell's 'agent' during a live online chat, and because of his recommendation, it never occurred to me to check the user ratings, which I always do when shopping on my own. Caveat emptor, folks!
Do Not Buy(05/01/2015)
Mainspring housing pin hole at bottom drilled off and won't align with frame. Even worse, hole for mainspring and mainspring retainer was not drilled all the way thru. Totally unusable and cannot be installed (or even function) as received. Returned to Brownells for credit/refund. Save your money.
mainspring housing(17/02/2016)
pin hole off .had to file and file to fit on my para and very dirty in spring hole
Product no.: 555102001 JOHN MASEN FLAT CHROME MOLY Mfr Part: 4547FB 20 LPI checkering greatly improves the grip and helps keep the pistol steady in the hand for improved recoil control. First choice of top combat shooters. Finish-machined from a solid steel casting, no fitting required.
Made in USA
US export classification: 0A501.y.1
This item is controlled by the U.S. government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. It may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.
Product no.: 555102002 JOHN MASEN ARCHED CHROME MOLY Mfr Part: 4547AB 20 LPI checkering greatly improves the grip and helps keep the pistol steady in the hand for improved recoil control. First choice of top combat shooters. Finish-machined from a solid steel casting, no fitting required.
20 LPI checkering greatly improves the grip and helps keep the pistol steady in the hand for improved recoil control. First choice of top combat shooters. Finish-machined from a solid steel casting, no fitting required.
SPECS: Chrome Moly blued or 410 stainless steel, flat or arched. Fits Govt./Commander 2-1/16" (5.2cm) long, .536" (13.6mm) wide.
More...
Customer ratings for JOHN MASEN FLAT CHROME MOLY
Number of ratings: 12
From brownells.com: 12
Average rating: 1.8
Good for the price(19/02/2012)
Fits my 1911 real good. I prefer an arched ms over a flat ms. Finish isn't excellent thats why I can't give 5 stars. The finish looks dull stainless not a nickel stainless.
Pin hole didn't line up(22/08/2011)
The pin hole did not line up. I had to machine it to get it to fit my Springfield.
not bad for the price(02/07/2014)
I bought this item to replace the plastic mainspring housing on my Rock River 1911 that came with a plastic mainspring housing. I bought it on silver thinking that it would look nice as a two tone part on the gun but it didn't. I then realized the mainspring housing on my Kimber was also plastic so I decided to put it on that gun. It fitted fine with no modifications. It matches the stainless still finish from the Kimber. The only disappointment was the serrations are not sharp enough for my liking. They won't shave layers of skin from you hand like sand paper but I like them a little sharper than what they are. All in all, for the price, it is a good fit.
not cast to advertised specs(11/07/2010)
the manufacturer, (or brownells) states that the MSH is .536 wide. It is, on the underside. The exposed side varies between .517 and .522 and leaves a very large gap between the MSH and the frame. The width at the ribs is .605, about .02 too narrow. Additionally, the checkering is cast very poorly.
quality control is way off on this one.
Great Value(16/04/2013)
I love the feel and the value can't be beat. It did require some fitting to install it on a STI Spartan 9mm (Pin hole needed a little work). The bluing is OK and flat, which matches my gun. I like it.
You get what you pay for.(21/05/2014)
Simply put, the pin hole to secure part into the frame was off 1/16, the part had dings, the finish was all scratched up,& the checkering had no sharpness to it at all. This part may be good for a visual aid only.
Very Poor Quality and Workmanship(13/09/2016)
Despite other poor reviews, I took a chance and ordered this mainspring housing. It just arrived, and I was instantly disappointed with the quality.
First and foremost, the checkering quality is very poor. It is not uniform, and the points are very blunt.
Second, there are tool marks on flat surfaces which will be visible after this mainspring housing is installed.
I am going to return this mainspring housing and purchase a different/better type. This would be a definite downgrade to the appearance of my M1911A1.
DON'T WASTE YOUR MONEY ON THIS PART!!!!!(13/01/2011)
Was doing an upgrade job on a customers 1911 and decided I would try one of these to see how it would work. BAD IDEA!!!!!!!!!! This part is a peice of junk indeed. Did not fit the MS slot to begin with and then the retaining pin hole didn't line up either so I chuncked it in the trash, [$]lesson. Again DON'T WASTE YOUR TIME NOR YOUR MONEY. Get a Wilson and be done with it.
I WONT BE USING THIS PRODUCT AGAIN(13/05/2013)
WHEN I TOOK THIS PRODUCT OUT OF THE BAG AND SLID IT ON THE FRAME I IMMEDIATLY NOTICED THAT THE MAINSPRING HOUSING PIN HOLE DID NOT ALIGN WITH THE HOLES IN THE FRAME. THE HOLE IN THE MAINSPRING HOUSING WAS A GOOD .020 TO .030 MISALIGNED. ALSO THE RAILS THAT SECURE IT TO THE FRAME ARE TOO NARROW AND THE MAINSPRING HOUSING IS VERY SLOPPY IN THE FRAME ALLOWING THE GRIP SAFETY TO HAVE EXCESSIVE TRAVEL UP AND DOWN THAT ALMOST RELEASES THE END OF THE GRIP SAFETY.
WORTHLESS TRASH(15/06/2013)
I ordered this last week to replace to too-large arched mainspring housing on my new (to me) Colt, my first 1911. As other reviewrs have mentioned, the hole for the mainspring housing pin is WAY OFF CENTER and in -2- directions. It is not drilled closely enough to the rail, and even if it were, the MSH would stick out about .10" - .15" from the bottom of the grip frame, interfering with the magwell installation. My fault- I was directed to this part by a Brownell's 'agent' during a live online chat, and because of his recommendation, it never occurred to me to check the user ratings, which I always do when shopping on my own. Caveat emptor, folks!
Do Not Buy(05/01/2015)
Mainspring housing pin hole at bottom drilled off and won't align with frame. Even worse, hole for mainspring and mainspring retainer was not drilled all the way thru. Totally unusable and cannot be installed (or even function) as received. Returned to Brownells for credit/refund. Save your money.
mainspring housing(17/02/2016)
pin hole off .had to file and file to fit on my para and very dirty in spring hole
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