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Sv Interchangable Breechface


infinity

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Guys,

I've been reading previous topics aobut the SV IBF and most have experienced the loose breechface that caused some malfunctions on your blasters. I tried searching but to no avail. my question is, has SV improved the durability of their IBF? 2nd, do they offer slides without the IBF?? thanks guys!!

Regards,

infinity B)

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Infinity,

I currently have 4 guns with the IBF and have never had a problem with any of them coming loose. The potential for a problem lies in the fact that a single hollow bolt holds the IBF in place and Loctite is recommended for keeping the part at the proper torque. The two most common issues can occurr when the bolt is either overtorqued, stretched, and subsequently fails or has been re-assembled without using Loctite and simply loosens up.

In both of these cases the cause of the problem is assembler error and is easily fixed.

I do not believe that there is a problem or design change necessary.

Leo

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Leo,

I beg to differ.

My SVI Competition, through which I shot some 60k rounds, experienced hollow bolt breaking in two pieces, with consequent breechface departure through the ejection port this spring at the Euro Med Cup.

I have always checked for it to becoming loose, and it had not.

I had properly loc-tited it and tightened (but overtightened) it.

When the separation happened, the hollow bolt part that remained into the breechface was still loc-tited to the breechface, that I had to file two small slots into it, allowing a properly sized flat screwdriver to turn it like it was a slotted screw (if this makes sense for you).

So, in my case, I really can't blame myself for not checking or properly setting it up.

Edited by Skywalker
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I have 2 SV Super open guns and 2 SV .40 LTD guns. All have the breachface. My oldest .40 has 112,000 rounds on it and I have never had a breachface come loose or cause a problem in any of these guns. The combined total of rounds fired in all these guns is nearly 200,000 rounds (I keep a log book) without a breachface problem..

Mick

A27257

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Skywalker,

I covered exactly what happened to you in my post. The bolt is not the strongest, because of the hollow design, but is also not under any real stress. In the vast majority of the cases where the bolt shears, the bolt was previously overtightened and stretched, almost to the point of failure, and vibration took care of the rest. There is a fine line between tight and overtight in this situation.

I never said that it had never happened, as you are proof, but it seems to be a fairly rare occurrance.

Leo

Edited by L9X25
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in my honest opinion they (SV) just wanted to have an edge over STI that's why they came out with the IBF...i still believe that with less moving parts less headache. But does SV sell slides with standard breechface?

NO, they all have the IBF. Since virtually all SV slides are custom made to the customer's specifications, they can easily make any caliber on any slide with the IBF change.

Sounds like a good marketing/engineering move to me.

No SV slide is caliber specific and can be changed to anything with the IBF, extractor, barrel and maybe ejector change.

Mick

A27257

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Scooter,

For someone to lose several IBF's, they would likely be installing them incorrectly, see post #2.

If someone felt the need, I would guess that you could use a stud and bearing type of loctite on the IBF itself (instead of simply using loctite on the bolt) and permanently install it, I just don't believe that it is necessary. I have lots of friends that have the IBF, in addition to the 4 that I own, and I have never experienced a failure not covered by post #2.

Strange things can happen, but they do not happen often enough to be a concern. If installed properly, the IBF is simply not an issue. I have seen and heard of far more cracked STI slides than lost IBFs. And an IBF problem can be fixed or replaced much faster and easier than a broken slide.

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I personally have six SV's with IBF's and have never had a problem with any of them. my single stack is set up for 9mm and .45, and I have switched it back and forth several times without incident. I have heard two or three stories of IBF failure as compared to the many people I know that shoot SV pistols without problems. For every horror story there is a greater number of success stories. I think you could buy a SV slide with the confidence that you will shoot many rounds without equipment failure.

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I've seen one, and it kept throwing its breach face during the match. Don't know the cause just caught my eye because I was RO'ing and notice two things ejecting from gun then a click and I stopped the shooter.

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I've seen one, and it kept throwing its breach face during the match. Don't know the cause just caught my eye because I was RO'ing and notice two things ejecting from gun then a click and I stopped the shooter.

Anything that is made by man can and will eventually break ... if you don't believe me, you can loan it to my brother and he will prove it!

Since the breechface is held in place by a bolt, the bolt had to have broken (overtightened) or loosened up (no loctite) for the IBF for exit. The fact that it flew out repeatedly shows that the guy was simply sticking it back into the gun and did not know how it was supposed to attach (user error).

As SGTSVI indicated, this is a very rare occurrence, even when you include the opportunity for user error. In my opinion it is not an issue.

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So what is the proper torque? This is something I may need to know someday.

I don't know that they have established a "proper torgue". I know I use a good allen wrench with enough pressure to get it tight and have some blue loctite on it. Let it sit for the loctite to dry and they are good to go.

Mick

A27257

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  • 10 months later...

I have a similar question that fits under this topic, i.e. Has SV changed the IC breechface?

First let me say I have 2 IC breechface slides, one with significant round count and one that has been shot a fair amount, and I have had no problems whatsoever. I recently ordered a third. Several people in the past have mentioned the little tab below the extractor breaking off. (See Benny's post in this thread and David and Schmitz's posts here. Neither of my my previous breechfaces had this part break. However, the new slide I ordered just came in with this piece missing... I guess they decided to stop it from happening by machining it off?

Just to make sure everyone understands what part I am talking about, it is the lower left "tab" below the extractor hole seen in the ejection port of this cutaway on SV's website:

breechface_cutaway_224_225.jpg

Also, the lower left side of the face of the breechface pictured here, also from SV's website:

breechface_216_278.jpg

Don't have a picture of my new one, but suffice it to say that part's just not there.

Edited by DBChaffin
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The IBF really scares me. Until they get it to work flawlessly i don't think i'll be looking towards their slides...thanks for the reply guys!! i appreciate it.

Infinity-

That comment is a little bit harsh, considering the present state of its design. People say:"if it ain't broken don't fix it." In my own version I state: "If ain't broken, fix it anyway, make it better." My consensus is that anything in line to be made better can not be broken before you make it to perform even better. You would need to fix it first, before making it better than it was prior to breaking.

The IBF idea altogether is far ahead of it own time. If you were to review the mechanics at work you would notice that everything should stay put, even with a "loose" retaining bolt. I know I have shot several thousands in my own with it loose, and its self centering stress bearing/transfer area into the slide, matched to their natural indexing design keeps it in place. The only issue that could indeed pull the breechface forward during fire would be if the bottom of it was "down-hanging" below (oversized) with a slight ledge forming that would catch on a cartridge rim as the slide moved rearwards with a broken IBF bolt. Normal inspection now and then would preclude you from letting this happen, and if there was an overhang it would show when tight, and ground flush.

I have been installing SVI/Infinity slides from even before their IBF. I happen to have a 6" Infinity slide in .40 S&W that does not have the IBF feature. I am pretty sure that some folks would wlelcome the opportunity to be able to replace a worn out breechface woithout having to replace the entire slide.

The issue of the "broken" ejector tunnel bit (in the IBF), is normally caused when "improperly" installing an Aftec extractor. The Aftec instructions ask that you remove a small section above and below the tunnel innermost areas to allow the extractor to pivot slightly vertically. If this is not done that little piece will eventually break off, even if it is not an IBF design.

To SVI/Infinity all I have to say is: Keep up the good work. Thank you.

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Venry, have you ever seen a new, uninstalled one with the extractor tunnel bit missing?

Well, you made me look !!!!

I just received a couple of new slides from Infinity last week. I checked them, and sure enough, the lower little bit has been removed, and the tunnel additionally opened to allow unhindered extractor movement. :cheers:

As it has been mentioned by others already, SVI/Infinity does their homework and R&D. This incidents have been mentioned to them before, icluding by yours truly. They are known to listen, especially Brandon and Sandy. It would be nice if more manufacturers were to listen as attentively.

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  • 4 months later...

i have the said slide and would like to chrome it. i was advised to remove the breechface first before chroming.

is this correct? can i just have the whole slide chromed breechface and all?

will there be any problems if i do this?

also it seems that i have to cut the firing pin spring in installing an extended firing pin on it since the screw of the breechface made the hole volume lesser than normal? any suggestions?

thanks in advance.

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I think the IBF is a great idea and am glad that SVI is able to keep costs in slide manufacturing down so they don't have to outsource the manufacturing overseas to save costs... Think about it, they make every slide the same (with Customer preferred cuts) and add the IBF for the caliber of choice. It's genious...

Edited by trickpony
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