Moderator failure

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First shot of factory Hornady , really loud compared to others rifle I have shot and sparking muzzle flash. Thought best have a look down- moderator baffle was hanging down. £700 for 1shot mod! And a wasted range day.

Bore scope down moderator from muzzle shows baffles deformed back towards the rifle muzzle as per photo. Now bore in 6.5mm, end of moderators 8.2mm so plenty of clearance. Only 0.010” around the over barrel part of moderator to barrel so defiantly concentric threading ( checked when done to 0.0005”)

Sent back and to manufacturer who claimed baffle strike- despite metal around the baffle deformed and bent back towards the muzzle of rifle. From my experience of bullets they bend things in the direction of travel not back. And if that significant a baffle strike would expect the bullet to then damage end of moderator or deform inside moderator and completely destroy it but not a mark on muzzle of moderator.

Not a baffle strike then as any strike would cause the bullet to deviate and or tumble. ..

Sent back and now being told it’s all happens because I did not have the soft plastic bushing installed at the rear of moderator to centralise it. My understanding is a moderator is set of the square shoulder at the back of the threads. Also no bushing was supplied.

Absolute tosh, the bushing is only there to stop and damage when inserting or removing the moderator and to stop crap getting in.

Have been the recipient of quite unsavoury messages when I have pointed the above out and even did the maths to calculated that with the size of the moderator hole sand the distance of the damaged baffle in front of the muzzle compared to the amount the moderator extends back over the barrel it is a physical impossibility by around 0.060” of moderator movement at the rear of it being able for a bullet to strike/ touch a baffle. ( remember only 0.010 of clearance there)

Correct the baffles need to be well out of alignment to be in the path of the bullet if you had 0.85mm radial clearance in the bore.
There isn't enough clearance between the vertex chamber and the barrel to allow the moderator to offset enough to allow the bullet to strike the last baffle let alone the first.

Told “it’s a mistake that is clearly yours” for not having the not supplied bushing machines and installed to centralise.

Not naming moderator at present as way things are going will end up with trading standards as relationship has broken down and have already had to have it made right once for it to them fail after one shot, not to mention risk if I had not done a safety check after that shot. Could have been significant injury. Lost faith and do not want a “free repair” or to send my rifle to him “to make right” after seeing the quality of machining. Requested a refund which I feel would be appropriate.

Over to you. And thanks for reading my story.

"It's a mistake that is clearly yours " bwahahaha sounds just like Mr Robbie S***
 
Moderate back with manufacturer as would not talk to me until sent back for their inspection. Hence I insured I saved a borescope video for my “evidence” as could be stripped and baffles changed/ replaced etc.
 
Thought I would get your collective thoughts on this.
Obviously this is my side of the story but would appreciate your expertise. I already have discussed this with a few gunsmiths and they have given their views.

Story- custom 6.5prc, carbon barrel, custom action, PSE stock- no expense spares as I like my kit!
Due to carbon barrel being 0.96” Decided to splash out on a custom mod. Told would have less space inside but would be good for 6.5prc pressure as survived 10 000 rounds in testing.Mod arrived and despite it being a special order the rear was not to size to fit over barrel, sent back and re machined to fit at measured 0.98” giving 0.010 of barrel clearance on each side. Snug I know.

Rifle cleaned, de oiled and bore sighted and off to a booked long range day.

First shot of factory Hornady , really loud compared to others rifle I have shot and sparking muzzle flash. Thought best have a look down- moderator baffle was hanging down. £700 for 1shot mod! And a wasted range day.

Bore scope down moderator from muzzle shows baffles deformed back towards the rifle muzzle as per photo. Now bore in 6.5mm, end of moderators 8.2mm so plenty of clearance. Only 0.010” around the over barrel part of moderator to barrel so defiantly concentric threading ( checked when done to 0.0005”)

Sent back and to manufacturer who claimed baffle strike- despite metal around the baffle deformed and bent back towards the muzzle of rifle. From my experience of bullets they bend things in the direction of travel not back. And if that significant a baffle strike would expect the bullet to then damage end of moderator or deform inside moderator and completely destroy it but not a mark on muzzle of moderator.

Sent back and now being told it’s all happens because I did not have the soft plastic bushing installed at the rear of moderator to centralise it. My understanding is a moderator is set of the square shoulder at the back of the threads. Also no bushing was supplied.

Have been the recipient of quite unsavoury messages when I have pointed the above out and even did the maths to calculated that with the size of the moderator hole sand the distance of the damaged baffle in front of the muzzle compared to the amount the moderator extends back over the barrel it is a physical impossibility by around 0.060” of moderator movement at the rear of it being able for a bullet to strike/ touch a baffle. ( remember only 0.010 of clearance there)

Told “it’s a mistake that is clearly yours” for not having the not supplied bushing machines and installed to centralise.

First photo is machining of thread section of moderator ( poor and uneven from rifle muzzle end and would not have been subjected to rifle blast)

Next photos are looking from muzzle in direction of bullet travel then damaged baffles ( blowed back towards rifle muzzle) then exit of moderator which has undamaged baffle and exit.

Not naming moderator at present as way things are going will end up with trading standards as relationship has broken down and have already had to have it made right once for it to them fail after one shot, not to mention risk if I had not done a safety check after that shot. Could have been significant injury. Lost faith and do not want a “free repair” or to send my rifle to him “to make right” after seeing the quality of machining. Requested a refund which I feel would be appropriate.

Over to you. And thanks for reading my story.
IF the rear bush is needed to align the moderator then you have a terrible screw cutting job , also if the rear bush touches the barrel then this will effect the finish on the barrel via rubbing . from an engineering point of view I would get your Screw cutting on the rifle checked concentric to the bore , free of slop and square . If that's all good the fault lies with the Moderator seller
BTW not a fan of close baffles to bore , it might make a rifle a bit better on sound reduction but the risk of a baffle strike is much increased in the field .
All you need is confirmation of the barrel threading job , before that you are introducing a variable in any claim against the moderator retailer ( forget who made the mod , its the sellers problem to put things right) You have no contract with anyone but the seller !
 
What I am really interested to know is why you paid £700 for a mod!
I have 2 ASE’s (SL5 and jetZ compact) and a dpt all end of barrel and the most expensive is only £405 now (I paid a lot less than this 3 years ago).

Seems inordinately expensive for a mod, even in today’s world.
 
As Bowland said, not all bores are central/ concentric to the barrel OD. The mod locates on the machined shoulder so that needs to be square to the threads on both the barrel and the mod. If those conditions are met you'd think a failure due to pressure is the cause. I think you may be in for a lot head banging. Good luck 👍
 
Thread have been checked to 0.0005” of an inch and concentric to the bore and in spec.
As Bowland said, not all bores are central/ concentric to the barrel OD. The mod locates on the machined shoulder so that needs to be square to the threads on both the barrel and the mod. If those conditions are met you'd think a failure due to pressure is the cause. I think you may be in for a lot head banging. Good luck 👍
 
To be fair I feel they are properly in spec as no wobble when screwing mod on, and only 0.010 inch clearance between rear of mod barrel so if not all concentric would fowl on barrel. The threads of moderator being concentric to the rest of the mod I can not comment on.
 
The threads of the moderator being concentric to the rest of the mod I can not comment on.

This was my point. And when they cut the threads they probably bored the barrel clearance too. So these will be concentric... but if they both weren't cut concentric with the boreline in the moderator then it was a waste of time.

All that said. As an engineer. I still view the pictures as more of a pressure than a strike issue!
 
£700 for this mod? Did the supplier have a big window in the front of the shop?

That looks like pressure failure but there is an impact of something on one of the photos (could be the way the photo is taken) the photos aren’t great as I don’t see the thread machining you are talking about?

IMG_3188.webp

Regards,
Gixer
 
I’m not sure which of these 2 baffles it is but that’s just the machining being all over the place! If you PM me a what’s app I am happy to send you video to review. It’s quite hard to get a view of threaded section of moderator as forward facing borescope. Last photo is of the thread section.
 

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£700 would be about right for a Lawrence Precision I suspect? Very happy with mine for about 10 years and god knows how many .308 so this is surprising.
 
£700 would be about right for a Lawrence Precision I suspect? Very happy with mine for about 10 years and god knows how many .308 so this is surprising.
If it is an LP, I was warned by a gunsmith, not to touch them!
He never said why.
 
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