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Posted: 11/26/2014 7:08:36 AM EDT

Why do some come with removable weights in the bolt?

I have a DDLES bolt. I was thinking about using a JP silent spring but it needs the bolt weight gone. I run suppressed and have had very good results with a JP silent spring in 556.

Posted: 11/26/2014 7:17:32 AM EDT

[#1]

Because the 9mm ARs are blowback and need the extra weight to keep the bolt locked up long enough to let pressures drop to safe levels.

Posted: 11/26/2014 11:21:35 AM EDT

[#2]

JP now has a bolt & silent spring setup for the 9MM. The bolt is already ramped and narrowed for Glock magazines.

Posted: 11/26/2014 12:52:20 PM EDT

[#3]

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Quoted:
JP now has a bolt & silent spring setup for the 9MM. The bolt is already ramped and narrowed for Glock magazines.

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This. Buy theirs and sell the DDLES or keep as a backup.

Posted: 11/26/2014 9:15:16 PM EDT

[#4]

The JP Silent Spring has a stiffer spring to make up for the loss of the weight in the bolt.

Posted: 11/27/2014 10:30:29 AM EDT

[#5]

Quote History

Quoted:
Because the 9mm ARs are blowback and need the extra weight to keep the bolt locked up long enough to let pressures drop to safe levels.

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That does not really answer the OP's question why SOME have removable weights.

Are they meant to be tunable with different weight sets? Seems pretty picky if you have to do that, and it adds another part to the bolt.

Posted: 11/27/2014 11:56:49 AM EDT

[#6]

Quote History

Quoted:

That does not really answer the OP's question why SOME have removable weights.

Are they meant to be tunable with different weight sets? Seems pretty picky if you have to do that, and it adds another part to the bolt.

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Quoted:

Quoted:
Because the 9mm ARs are blowback and need the extra weight to keep the bolt locked up long enough to let pressures drop to safe levels.

That does not really answer the OP's question why SOME have removable weights.

Are they meant to be tunable with different weight sets? Seems pretty picky if you have to do that, and it adds another part to the bolt.

Other than the JP, which uses a stronger spring to accomplish the same effect, I've never seen a 9mm bolt without it.

Posted: 11/27/2014 12:45:24 PM EDT

[#7]

As far as I know ALL have removable weights......weights are there as the mass is required for the blow back action.....and I don't know of a way to machine one in one piece without drilling through from the rear.....then you have to fill it with something.....

Posted: 12/1/2014 11:38:45 AM EDT

[#8]

Quote History

Quoted:
JP now has a bolt & silent spring setup for the 9MM. The bolt is already ramped and narrowed for Glock magazines.

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Thanks. I bet that's the best option. The combo is $400 before shipping. I'm wondering if I need it that much.

Anyone have experience with this setup in 9mm? I know it's nice in 556/223 (mainly the silent spring).

Posted: 12/1/2014 3:57:01 PM EDT

[#9]

I'm running the JP SCBS and JP 9mm bolt in my DDLES Glock 9mm SBR with a 5" adco barrel and Liberty Mystic suppressor. Its certainly not the cheapest option but it has functioned perfectly and is very smooth. I've only shot 147 & 158 gr ammo, so i can't comment on function with 115 or 124 gr ammo.

FWIW, before switching to the SCBS I was running a St-9x buffer with a wolf extra power buffer spring and this setup ran flawlessly too..

Also, since i see it mentioned alot, my BHO has worked every time with no tweaking required.

Posted: 12/1/2014 4:18:54 PM EDT

[#10]

Quote History

Quoted:
I'm running the JP SCBS and JP 9mm bolt in my DDLES Glock 9mm SBR with a 5" adco barrel and Liberty Mystic suppressor. Its certainly not the cheapest option but it has functioned perfectly and is very smooth. I've only shot 147 & 158 gr ammo, so i can't comment on function with 115 or 124 gr ammo.

FWIW, before switching to the SCBS I was running a St-9x buffer with a wolf extra power buffer spring and this setup ran flawlessly too..

Also, since i see it mentioned alot, my BHO has worked every time with no tweaking required.

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That is exceptionally close to what I have. I have a full ddles manufactured 9mm pistol. I've applied for SBR status. I also have a Liberty Mystic for it. I've run just about everything I can get a hold of through it. Functions fine.

Does the SCBS make it smoother? To make it smoother I'd like the SCBS, but then I'd have to get a bolt too. I'm embarrassed to admit how much I've paid for this setup so adding anymore upsets me. Then again. I've spent so much, may as well make it "perfect."

Posted: 12/1/2014 6:15:55 PM EDT

[#11]

Quote History

Quoted:
That is exceptionally close to what I have. I have a full ddles manufactured 9mm pistol. I've applied for SBR status. I also have a Liberty Mystic for it. I've run just about everything I can get a hold of through it. Functions fine.

Does the SCBS make it smoother? To make it smoother I'd like the SCBS, but then I'd have to get a bolt too. I'm embarrassed to admit how much I've paid for this setup so adding anymore upsets me. Then again. I've spent so much, may as well make it "perfect."

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I already had a JP bolt when they released the SCBS so my wallet didn't take a huge hit by upgrading. But it definitely removes the "sproing" noise and in my opinion makes the gun feel smoother.

I try not to think about how much i've spent on guns..

Posted: 12/1/2014 7:58:13 PM EDT

[#12]

Quote History

Quoted:

I already had a JP bolt when they released the SCBS so my wallet didn't take a huge hit by upgrading. But it definitely removes the "sproing" noise and in my opinion makes the gun feel smoother.

I try not to think about how much i've spent on guns..

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Quote History

Quoted:

Quoted:
That is exceptionally close to what I have. I have a full ddles manufactured 9mm pistol. I've applied for SBR status. I also have a Liberty Mystic for it. I've run just about everything I can get a hold of through it. Functions fine.

Does the SCBS make it smoother? To make it smoother I'd like the SCBS, but then I'd have to get a bolt too. I'm embarrassed to admit how much I've paid for this setup so adding anymore upsets me. Then again. I've spent so much, may as well make it "perfect."

I already had a JP bolt when they released the SCBS so my wallet didn't take a huge hit by upgrading. But it definitely removes the "sproing" noise and in my opinion makes the gun feel smoother.

I try not to think about how much i've spent on guns..

Totally. I've spent more on this than I needed too. Right after I paid for it, because I had to have it, I really discovered tranferables. Doh.

Since those parts are not on sale I can buy them after the stamp comes in.

Posted: 12/1/2014 10:59:46 PM EDT

[#13]

I do find that my 9mm SBR is smoother with the silent spring than it was with a regular spring and buffer. Enough so to warrant the increased cost? I don't know, but I already have it so I'm keeping it.

Posted: 12/1/2014 11:19:47 PM EDT

[#14]

The weight in my Colt would only be removable if you drove the giant roll pin out of the carrier.

Posted: 12/2/2014 2:35:29 PM EDT

[#15]

How does the Glock mag modified bolt differ from the normal colt bolt

Posted: 12/2/2014 3:14:46 PM EDT

[#16]

Quote History

Quoted:
How does the Glock mag modified bolt differ from the normal colt bolt

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The bottom of the carrier is narrower to clear the feed lips of Glock mags.

Posted: 12/3/2014 3:27:42 PM EDT

[#17]

Posted: 12/4/2014 3:29:21 PM EDT

[#18]

Thanks for the graphic. Really makes sense.

So I put an add up in EE for both. Long shot but I have time.

Posted: 12/9/2014 12:48:24 PM EDT

[#19]

Maybe a new thread topic.

What is your feeling on using a normal high quality bolt carrier and having ADCO cut it for use on the DDLES. That have a specific service to do that.

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