Want to Upgrade SF 623FA TAc Light to LED

[Walt NVA]

During March 2003, I purchased a Mossberg 590A-1 shotgun with a Surefire 623FA Tactical Light. I want to convert the light to LED.

I unscrewed the Bezel of the 623FA to see what lamp was inside, i.e., the SF P60 lamp. I replaced the P60 lamp with a Malkoff drop-in M60L LED. However, when I racked the shotgun (not firing it), the M60L would often fail to illuminate. The only thing that I can determine is that the M60L does not have a shock absorbing spring like the SF P60.

I had placed the removed P60 lamp on a shelf with two other loose Surefire P60 lamps. Since I thought that all Surefire P60 lamps were one and the same, I apparently put back in a P60 lamp other than the P60 lamp that I removed. Only the Surefire P60 lamp stamped "RH-2" works consistently in the 623FA -- meaning that it must have been the one that I removed from the 623FA. The other P60 lamps (stamped other than "RH-2") will work only intermittently when I rack the shotgun, i.e., they sometimes fail to illuminate with either the on/off switch or with the side pressure bar switch.

My first Question: what does the "RH-2" designation refer to on the P60 lamp and why is it that the other Surefire P60 lamps (not marked as "RH-2") will only work intermittently in the 623FA? Again, this is with only racking the shotgun and not firing it.

My second question: how can I convert my Surefire 623FA Tactical Light to LED? I know that SF makes the P60L, but I would like something better. I am bummed that the Malkoff M60L will not consistently work in the SF 623FA Tac Light. If the SF P60L is the only suitable option, will any P60L be sufficient or will I run into issues as with the P60 mentioned above (where only the P60 stamped "RH-2" consistently works)?

Thanks.

 

[USM0083]

The bezel of the 623FA is shock isolated, so that may be your problem, as it may make for a loose fit, and inconsistent electrical contact.

This should fix the problem:
http://www.malkoffdevices.com/shop2/index.php?main_page=product_info&cPath=1_14_18&products_id=6

 

[Size15's]

You don't need the Z32 shock isolated bezel used by the 623FA when running the P60L. In fact the P60L will run higher output without it but should have no problems running with it either so you don't really need to buy a Z44-BK non-shock isolated bezel unless you really want to.
However, the design of the L60 Lamp Module (that the Z32 is part of) is not ideally suited to the Z44. If you get one, I suggest not cranking down on the bezel too hard if you can screw it on past the 'lip' on the L60 Lamp Module Housing Body that the Z32 bezel would be stopped by.

 

[Justin Case]

What is the issue with screwing down the Z44 past the lip of an L60? At least with my setup, the lip extends past the inside threads of the Z44. Thus, the Z44 physically can't get past the lip, unless you crank the bezel down so hard as to break the lip. But in that case, such a caution would apply to any bezel.

 

[Justin Case]

I doubt RH-2 has any meaning in terms of fitment. My guess, and it's just a guess, is that it is the stamp of some QA/QC inspector. I have P60s stamped with SC-4, NC-4, NK-2, as well as no stamp at all.

Check the "shoulder" at the top of the weaponlight body for any crud/contamination. The Malkoff brass body and the P60 outer spring need to make ground contact on that shoulder. Check the outer springs for your P60s and look for any differences as well that could compromise contact with the shoulder.

For use in a weaponlight, the Malkoffs are also supposed to need a beryllium-copper fitting ring, which was mentioned in post #2. It is also possible that you may need to stretch the center spring a bit. If you compare an M60 with a P60, you'll see that the overall height of the M60 (including the center spring) is a little shorter than that for a P60.

 

[Size15's]

Not all classic WeaponLight components are exactly the same.
Having said that, it's with the "M2" bezel I've had the most obvious issue so perhaps it is different from the standard bezel

 

[Walt NVA]

I thought the same about the "RH-2" stamp on the stock P60 lamp, i.e., that it probably does not mean anything. However, what is strange is that it is the only P60 that consistently works in the 623FA after racking the Mossberg. Then again, the other two P60 lamps that did not work came from a SF 6P and a SF G2 (after Malkoff upgrades); maybe those springs were tensioned in those respective flashlights to where they would not consistently work in the 623FA, although visibly there does not appear to be a distinguishable difference between the springs on the three SF P60 lamps. Go figure.

I checked the 623FA housing for any contamination but did not find any.

I touched base with Gene Malkoff. He is mailing a Beryllium Copper Spring Washer to see if it will remedy use of the Malkoff M60L in the 623FA. Good observation and idea on the difference between the M60L and SF P60 springs; hopefully, I won't have to mess with the M60L spring.

Thanks for all the responses!

 

[Size15's]

The codes stamped on the Lamp Assemblies are batch qc codes.

Yes, the springs could require careful stretching. They are not specifically tensioned for specific models. However, a shotgun will give the springs more of a pounding of course and it's better to start with good tension (good contact)

 

[Walt NVA]

The Beryllium Copper Spring Washer resolved this issue. After several tests with the Mossberg 590A-1 shotgun (primarily numerous racks), the Malkoff M60L drop-in works consistently and flawlessly in the Surefire 623FA Tactical Light. I very much appreciate Gene Malkoff sending the Washer gratis after I explained the issue to him. May Gene and his wife keep walking on water! And, thanks to all who responded to this issue. CandlePower Forums is outstanding.
=====
Info. received today from Surefire on this issue:
You should not be experiencing any compatibility between any P60 lamps, RH-2 markings or not. My only explanation is that those two P60 lamp assemblies may be defective, or may have had their contact springs compressed if stored overtime. You will need the BP60L to convert your 623FA to an LED light, the BP60L will be released later this year and will provide you with a P60L lamp assembly and an aluminum bezel.

 

[USM0083]

Glad the problem has been resolved.

 

[Walt NVA]

Well, I'm back with the same issue, i.e., intermittent on/off even with the Beryllium Copper shock ring from Malkoff. Will perhaps a second Beryllium Copper shock ring resolve the issue? I am at a loss as to why the problem has reoccurred. I have not yet tried to strech the spring on the Malkoff M60L.

 

[Kato]

Try stretching the spring on your M60L. Doing that solved the same problem with the M60 in my SF 618.

 

[Walt NVA]

Thanks. I did some serious graduated stretching with needle nose pliers on the spring of the M60L. It substantially helps in conjunction with the Beryllium Copper shock ring. By comparison, the spring assembly of the stock SF P60 is heavier gauge. There remains an ever so slight flicker when the shotgun is racked or even if the trigger is pulled (dry fire). However, those situations are by all means tolerable. Hopefully, this does it.

 

[Yoda4561]

Try wrapping the module with a strip of aluminum foil, folded over itself a few times. It should be thick enough to fit without falling out if held upside down, but loose enough to be removed by hand. This will solve any negative/body contact issues with the module.

 

[Walt NVA]

Thanks Yoda. I'll try that as well, except that the Mossberg shotgun had to be sent away for warranty service and with it of course the SF623FA forearm assembly.

 

[Justin Case]

Thanks. I did some serious graduated stretching with needle nose pliers on the spring of the M60L. It substantially helps in conjunction with the Beryllium Copper shock ring. By comparison, the spring assembly of the stock SF P60 is heavier gauge. There remains an ever so slight flicker when the shotgun is racked or even if the trigger is pulled (dry fire). However, those situations are by all means tolerable. Hopefully, this does it.

If the drop-in isn't reliable when jostled merely by the action cycling or the hammer falling, what is going to happen under the recoil of full power loads? If it were me, I would not trust it until it proves reliable under live fire conditions.

I would apply some easily rubbed off coloring to the "well" in your weaponlight body, maybe Crayola markers for kids that wash off with water. Then insert the Malkoff and look to see where the Malkoff touches (or doesn't touch), i.e., rubs off the coloring.

It seems clear that you have an intermittent electrical circuit.

If you look inside the well of a weaponlight body, you'll see a "rim" that holds back the batteries. I suspect that this rim is preventing the Malkoff body from going deep enough into the well to make reliable contact, especially if stretching that center spring has helped somewhat. But there may be intermittent electrical contact to ground, as well as to the + battery terminal. You might have to do a little filing to re-shape the bottom face of the Malkoff to better fit the profile of the weaponlight well.

You'd think that the beryllium copper ring would accomplish the same thing, but apparently it hasn't.

Wrapping with aluminum foil is another fairly standard trick, already mentioned above, to help improve thermal conduction and ground connection.

Is the weaponlight body's "well" completely anodized, except for the battery retaining rim? If that's the case, then wrapping with aluminum foil may not solve the problem since the anodizing may prevent a good ground contact.

 

[Justin Case]

The Beryllium Copper Spring Washer resolved this issue. After several tests with the Mossberg 590A-1 shotgun (primarily numerous racks), the Malkoff M60L drop-in works consistently and flawlessly in the Surefire 623FA Tactical Light. I very much appreciate Gene Malkoff sending the Washer gratis after I explained the issue to him. May Gene and his wife keep walking on water! And, thanks to all who responded to this issue. CandlePower Forums is outstanding.
=====
Info. received today from Surefire on this issue:
You should not be experiencing any compatibility between any P60 lamps, RH-2 markings or not. My only explanation is that those two P60 lamp assemblies may be defective, or may have had their contact springs compressed if stored overtime. You will need the BP60L to convert your 623FA to an LED light, the BP60L will be released later this year and will provide you with a P60L lamp assembly and an aluminum bezel.

I doubt that the springs compressed because they were "stored overtime" under a static load.

Steel springs don't just start to creep at room temperature. Otherwise, you'd find your car's suspension sitting on its rubber stops some morning because the springs just "compressed". This is the same as the myth about pistol and rifle magazine springs taking a "set" because they are stored loaded. That's nonsense. A spring may take a set from the initial loading, but nothing happens after that. It's a static load. You can leave that magazine loaded for decades and the spring won't get shorter because of long term static compressive load

If anything, I'd think that the P60 in the shotgun weaponlight would have a higher likelihood of spring compression due to weapon recoil producing cyclic loads on the lamp.

 

[Walt NVA]

If the drop-in isn't reliable when jostled merely by the action cycling or the hammer falling, what is going to happen under the recoil of full power loads? If it were me, I would not trust it until it proves reliable under live fire conditions.

I would apply some easily rubbed off coloring to the "well" in your weaponlight body, maybe Crayola markers for kids that wash off with water. Then insert the Malkoff and look to see where the Malkoff touches (or doesn't touch), i.e., rubs off the coloring.

It seems clear that you have an intermittent electrical circuit.

If you look inside the well of a weaponlight body, you'll see a "rim" that holds back the batteries. I suspect that this rim is preventing the Malkoff body from going deep enough into the well to make reliable contact, especially if stretching that center spring has helped somewhat. But there may be intermittent electrical contact to ground, as well as to the + battery terminal. You might have to do a little filing to re-shape the bottom face of the Malkoff to better fit the profile of the weaponlight well.

You'd think that the beryllium copper ring would accomplish the same thing, but apparently it hasn't.

Wrapping with aluminum foil is another fairly standard trick, already mentioned above, to help improve thermal conduction and ground connection.

Is the weaponlight body's "well" completely anodized, except for the battery retaining rim? If that's the case, then wrapping with aluminum foil may not solve the problem since the anodizing may prevent a good ground contact.

Thanks for the informative reply. What about adding a second Beryllium copper ring?

 

[Justin Case]

I'm not clear as to what a second copper ring could do that aluminum foil can't. Plus, the ring seems to be sized to work only at the bottom of the well. You can wrap foil anywhere -- around the sides of the Malkoff body (which is where I would start), at the bottom, etc.

My Malkoff M30 works fine without the ring in an old weaponlight body that I converted to a handheld light, but I had to try a few different combinations of other parts (bezels, bezel spacer rings, etc). IMO, the solid brass construction of the Malkoff is great except when you run into apparent manufacturing tolerance issues like yours. When that happens, the Malkoff is not that as robust as other drop-ins IMO wrt slight geometry differences.

 

[Walt NVA]

Just received my Mossberg 590A-1 from warranty service. Thanks to Gene Malkoff, I also appear to have resolution regarding the intermittent working of a Malkoff M60L in the Surefire 623FA tactical light. Gene provided a ring that fits ON TOP OF (in front of) the M60L drop-in before screwing the tac light head onto the tac light body. I find that I do not need the Beryllium spring washer. With the M60L drop-in, I now have 140+/- lumens with an approximate runtime of 4 1/2 hours on 2 CR123 primary batteries

(UPDATE: see post no. 26)