9mm ramped bolt - Page 1

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Posted: 9/5/2014 10:22:44 PM EDT

It seems from my interweb searches that there are really only 2 options for 9mm ramped bolts, RRA or CMMG. Is there really any difference between them (is one better)? ADCO only sells the RRA, but some other dealers only sell the CMMG. Do I need to lean one way or the other, or just buy whichever I can find cheapest?

Posted: 9/5/2014 10:25:03 PM EDT

[#1]

Ramped bolts? In for info.

Posted: 9/5/2014 10:32:52 PM EDT

[#2]

I use a CMMG and it's 100%. Cheapest I've found is at Exile Machine.

Posted: 9/5/2014 10:33:14 PM EDT

[#3]

JP makes a bolt with a ramped charging pad.

Posted: 9/5/2014 10:35:25 PM EDT

[#4]

Colt seems to ramp their bolts now, as well, and you can also have an unramped bolt ramped by a smith or machinist.

To those in for info: Ramping is cutting a slope and sometimes radius into the underside of the bolt so that it's gentler on the hammer in the cocking cycle of counterbattery movement. The impulse of a pure blowback firing cycle is different than that of a locked-bolt DI or piston system, and can be hard on both hammer/trigger pins and their mounting holes. More modern iterations tend to ramp the bolt to reduce the shock to the pins and receiver of the blowback operating cycle.

Posted: 9/5/2014 10:38:51 PM EDT

[#5]

I did another search and found the JP BCG after remembering someone talking about having one that they paired up with the JP's silent spring.

I'll check out Exile. Thanks.

Posted: 9/5/2014 10:39:58 PM EDT

[#6]

Well, Exile is sold out.

Posted: 9/5/2014 10:40:33 PM EDT

[#7]

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Quoted:
I did another search and found the JP BCG after remembering someone talking about having one that they paired up with the JP's silent spring.

I'll check out Exile. Thanks.

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Are you going to use Glock mags? If so, you could consider the JP bolt or getting a CMMG bolt and having it cut. If you will not be using Glock mags, I'd say just go for the cheaper(but just as good) CMMG bolt.

Posted: 9/5/2014 10:42:31 PM EDT

[#8]

Interesting point, I searched on Brownell's, and they're selling JP's bolt for less then CMMG's. Interesting...I'll probably just go with the JP.

Posted: 9/5/2014 10:43:21 PM EDT

[#9]

Quote History

Quoted:

Are you going to use Glock mags? If so, you could consider the JP bolt or getting a CMMG bolt and having it cut. If you will not be using Glock mags, I'd say just go for the cheaper(but just as good) CMMG bolt.

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Quoted:

Quoted:
I did another search and found the JP BCG after remembering someone talking about having one that they paired up with the JP's silent spring.

I'll check out Exile. Thanks.

Are you going to use Glock mags? If so, you could consider the JP bolt or getting a CMMG bolt and having it cut. If you will not be using Glock mags, I'd say just go for the cheaper(but just as good) CMMG bolt.

No, I'm using Colt style mags. I have found the CMMG for as cheap as $180, but with shipping (free shipping through Brownells). Shipping almost makes the price the same, but if I purchase everything through Brownells I can get $50 off the entire order, which is an even better equalizer.

Posted: 9/6/2014 4:30:33 PM EDT

[#10]

http://fatboytactical.net/index.php?main_page=product_info&cPath=56&products_id=503

CMMG ramped bolt $165.00

Posted: 9/6/2014 6:54:10 PM EDT

[#11]

Bud's Guns has the CMMG in stock. I used "make an offer" of $160 and it was accepted. Shipping was higher than I like, $14 I think, but overall it was the best deal I found at the time. I had it in a few days.

Posted: 9/6/2014 7:03:14 PM EDT

[#12]

Every new RRA bolt I have seen was not ramped and requires the ues of the matching RRA's hammer......

Posted: 9/6/2014 9:47:20 PM EDT

[#13]

Quote History

Quoted:
Interesting point, I searched on Brownell's, and they're selling JP's bolt for less then CMMG's. Interesting...I'll probably just go with the JP.

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I got an email from Mel at JP stating that the ETA on these was a couple weeks. Brownells is in stock and if you use coupon code GRX you'll get 10% off. Brought it to 230 and change shipped to me.

Thanks for the heads up, saved me some money and time.

Posted: 9/6/2014 9:54:41 PM EDT

[#14]

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Quoted:
Every new RRA bolt I have seen was not ramped and requires the ues of the matching RRA's hammer......

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+1 This.

Posted: 9/6/2014 10:09:15 PM EDT

[#15]

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+1 This.

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Quoted:

Quoted:
Every new RRA bolt I have seen was not ramped and requires the ues of the matching RRA's hammer......

+1 This.

Yup. I had ADCO ramp mine so I could use a standard hammer - and use the 9mm upper on other lowers.

Posted: 9/6/2014 10:40:38 PM EDT

[#16]

I ended up going with the JP for a couple reasons. With the LEO discount and the discount code, It ran me just about $200.

Posted: 9/6/2014 10:55:43 PM EDT

[#17]

I had my smith ramp my unramped bolt. I use a regular round hammer.

Posted: 9/7/2014 9:12:54 PM EDT

[#18]

A RRA bolt also works with a DPMS hammer.

Posted: 9/7/2014 10:27:21 PM EDT

[#19]

I was one of the lucky ones to get a DDLES dedicated lower before they went under and bought it with the internal parts installed. DDLES told me they used DPMS parts so I'll have to take their word on that. I've decided to go with a RRA upper but would like to know: Should I get it with one of their (RRA) bolts and have it ramped by ADCO, or get an already ramped bolt from another maker? What does ADCO charge for this service?

Posted: 9/8/2014 4:16:04 AM EDT

[#20]

Quote History

Quoted:
I was one of the lucky ones to get a DDLES dedicated lower before they went under and bought it with the internal parts installed. DDLES told me they used DPMS parts so I'll have to take their word on that. I've decided to go with a RRA upper but would like to know: Should I get it with one of their (RRA) bolts and have it ramped by ADCO, or get an already ramped bolt from another maker? What does ADCO charge for this service?

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If using standard AR hammer...

RRA would need ramped AND cut
CMMG only needs cut
JP needs nothing

Posted: 9/8/2014 6:49:19 AM EDT

[#21]

Quote History

Quoted:

If using standard AR hammer...

RRA would need ramped AND cut
CMMG only needs cut
JP needs nothing

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Quote History

Quoted:

Quoted:
I was one of the lucky ones to get a DDLES dedicated lower before they went under and bought it with the internal parts installed. DDLES told me they used DPMS parts so I'll have to take their word on that. I've decided to go with a RRA upper but would like to know: Should I get it with one of their (RRA) bolts and have it ramped by ADCO, or get an already ramped bolt from another maker? What does ADCO charge for this service?

If using standard AR hammer...

RRA would need ramped AND cut
CMMG only needs cut
JP needs nothing

It only needs to be cut if it's a Glock lower. If it's a Colt-pattern lower, ramping is all a Rock River bolt needs.

ADCO did my RRA bolt ramp, and they shipped it back quickly. Their pricing is on their web site, under Shop Services, then under "9mm bolt mods." Just ramping showa as $50.

Posted: 9/8/2014 10:54:45 PM EDT

[#22]

Thanks. My lower is a Colt pattern. How do I know if my hammer is a "standard" hammer. As stated in my previous post, DDLES maintained they used DPMS internals. Does DPMS make more than one kind of hammer?

Posted: 9/8/2014 11:53:53 PM EDT

[#23]

Quote History

Quoted:
Thanks. My lower is a Colt pattern. How do I know if my hammer is a "standard" hammer. As stated in my previous post, DDLES maintained they used DPMS internals. Does DPMS make more than one kind of hammer?

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Standard hammer.

9mm hammer.

Posted: 9/11/2014 10:51:55 PM EDT

[#24]

Thanks for the last three helpful posts guys.

Posted: 9/11/2014 10:52:55 PM EDT

[#25]

Thanks for the last three helpful posts guys.

Posted: 9/13/2014 10:23:56 PM EDT

[#26]

Quote History

Quoted:
A RRA bolt also works with a DPMS hammer.

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Exactly, it is not necessary to ramp your bolt if you have a rounded (DPMS style) hammer. It makes it a little smoother, but it is not necessary. I've been using this little guy with an unramped bolt and DPMS hammer for half a decade, at least 5000 rounds through it, most of which suppressed.