1911 recoil spring to control the slide - and things that have a direct effect on this.

I'm trying to understand this better.  I thought I understood, but the more I think about it, the more confusabobbled it gets.

Start with a 1911 that is working fine.
Add a rail and a red dot sight.

• At this point, are any changes needed for either the spring or the load, to keep the gun running as it was before?  This includes the slide remaining open after the last round.  
  
• Suppose one adds a bigger sight, such as Aimpoint 9000sc.  Again, are any changes suggested to keep the gun working the same way?  Again, this includes the slide remaining open.
  

Trying to reason this out in my head, adding that much mass to the slide implies that either the load be stronger, or the spring be lighter.  That sounds "logical" to me, which doesn't make it "right".  



I also have another thought bouncing around in my head.  I watch all these YouTube videos, where someone places their left hand on the slide and racks it back and forth effortlessly.  On my Les Baer, I need a pair of elephants to help rack it at all, let alone effortlessly.  With my two Salyer guns, I can do it more easily, but nothing like what I see guys doing on YouTube.

• This could mean I'm the 98 pound weakling in the old Charles Atlas ads.
  
• Or, it could mean that the slide is such a tight fit, that this alone slows it down.
  
• Or, it could mean that every day I head to the range, I should add some oil to the slide mechanism.
  
• Or it could mean that my spring is heavier than what others use.
  

In a properly fitted and working Bullseye gun, 45, how much resistance should one feel when racking the slide?
Are there any well-written technical articles that describe these things?

Everything needs to be in balance.
Everything effects that balance
Recoil spring effects the slide movement (obviously)
Mainspring weight slows down unlocking, but only until the hammer is cocked
Firing pin stop bottom edge shape adds or removes effort to overcome mainspring until hammer is cocked
Mass of the slide & all the stuff you bolt on to it effects how the gun unlocks
The list goes on and it does end up being rocket science to make the firearm work the way you want on purpose and that's why I envy the understanding that a real bullseye gunsmith has for their craft.

Since knowing the spring rate seems to be a big part of this, Terry Labbe from Magnus Bullets pointed me towards this one:

http://www.securefirearmproducts.com/Model_Details.php?modelno=11490-SR-D

mikemyers wrote:I'm trying to understand this better.  I thought I understood, but the more I think about it, the more confusabobbled it gets.

Start with a 1911 that is working fine.
Add a rail and a red dot sight.

• At this point, are any changes needed for either the spring or the load, to keep the gun running as it was before?  This includes the slide remaining open after the last round.  
  
• Suppose one adds a bigger sight, such as Aimpoint 9000sc.  Again, are any changes suggested to keep the gun working the same way?  Again, this includes the slide remaining open.
  

Trying to reason this out in my head, adding that much mass to the slide implies that either the load be stronger, or the spring be lighter.  That sounds "logical" to me, which doesn't make it "right".  



I also have another thought bouncing around in my head.  I watch all these YouTube videos, where someone places their left hand on the slide and racks it back and forth effortlessly.  On my Les Baer, I need a pair of elephants to help rack it at all, let alone effortlessly.  With my two Salyer guns, I can do it more easily, but nothing like what I see guys doing on YouTube.

• This could mean I'm the 98 pound weakling in the old Charles Atlas ads.
  
• Or, it could mean that the slide is such a tight fit, that this alone slows it down.
  
• Or, it could mean that every day I head to the range, I should add some oil to the slide mechanism.
  
• Or it could mean that my spring is heavier than what others use.
  

In a properly fitted and working Bullseye gun, 45, how much resistance should one feel when racking the slide?
Are there any well-written technical articles that describe these things?

i run my wadgun with aimpoint micro and Kodiak Base with 11 lbs spring. with a 9000sc i think will run with 10 lbs. i have 10,11 and 12 lbs recoil spring.

I believe a 1911 is considered a delayed blowback not a locked breech Either way it's not rocket science, the more weight you add to the slide (rail, heavy 9000sc) the hotter your loads need to get and/or a weaker recoil spring to get the same function as a bare slide. Most people won't go under a 10# spring as you can start having reliability issues.

Regarding how hard your 1911 is to rack, that's not just your age lol, its a hard fit barrel not a loose fit factory setup so it take more to get the barrel to unlock. If you strip the gun and put it together without the barrel you'll see how smooth the slide & frame will cycle without the having to break the lockup.

Most bullseye shooters with a light mounted on their slide use anywhere from a 10lb to a 12lb spring. Try different rates for whatever feels good and works. I use a 10lb with an ultra dot on mine. I think it's also a good idea to use a buffer on your spring guide so the slide doesn't impact the frame hard.

Mike, there is one thing I should mention for you. When the gun fires the slide comes back and beats you and your scope up. Really slams that scope around. The point is. You can not hurt that scope by using it as a handle to rack your slide. The bigger the scope the easier to get a hold of. You too can make it look easy.

Wolfe Spring sells a calibration pack of 1911 recoil springs. They suggest find the spring that the gun just functions and go one pound lighter. Mainspring has a lot to do with timing and so does firing pin stop geometry. This was already said.

I hang around the 1911 forums and learn a lot about function.

David

zanemoseley wrote:.........Regarding how hard your 1911 is to rack, that's not just your age lol, its a hard fit barrel not a loose fit factory setup so it take more to get the barrel to unlock. If you strip the gun and put it together without the barrel you'll see how smooth the slide & frame will cycle without the having to break the lockup....

Thanks - that is something I never even considered!  
Next time the gun is apart, I'll try that.
Lots of things I have yet to learn - that was certainly one of them!  

For what it's worth, Terry from Magnus Bullets recommended a spring tester from someone who's very involved in Bullseye.  I ordered it yesterday, although they haven't finished making one of the components, so it will take a while to receive it.  

Terry and Dave Salyer both feel I should bump my load from 4.0 bullseye up to 4.2, with Terry's #801 bullets, for what I'm shooting now.  Will try that in an hour or so.

My "problem" is that instead of trying to make things better, I'm trying to understand.  What to do seems to be more obvious to people, but when I ask "why" the answers aren't so clear.