New Allen Magnum and APS rifle design finally ready to test....

Fiftydriver

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To all,

Well, I just finished the first 277 Allen Magnum to come out of APS. This new Allen Magnum was designed at the request of my good friend Richard Graves with the intent of him building a very large 185 gr ULD RBBT speicifically for this new chambering.

Basically, the 277 Allen Mag is nothing more then the 7mm Allen Mag necked down to 277 with no other changes. Performance with same weight bullets will be roughly 150 fps over what the 270 Allen Magnum will produce as the 277 AM is based on the slightly larger and much stronger 338 Lapua parent case.

The new round is not the only unique thing about this rifle. This rifle is the very first design of my Extreme Sporter V-Block rifle system.

The idea was to take the design of the Heavy V-Block but modify it and streamline it to work in a rifle in the 10-12 range instead of 25 to 30 lbs for my Heavy V-Blocks. And doing this while still offering the extreme stability that the V-Block barrel bedding system offers as well. The stock design of choice for this system was the McMillan A-5.

371975.jpg

This pic shows the stock with the V-Block bolt ports milled in the stock and the V-Block attached to the barrel next to the stock, showing how it will be positioned in the stock when finished. As with the Heavy V-Block, the Xtreme Sporter V-Block has a totally free floated receiver. Nothing behind the recoil lug bares solidly on the stock in any way. The barrel is held solidly into the V-Block by two 1/4-28 bolts.

371976.jpg

The main issue with the Xtreme Sporter V-Block is that the block needs to be dimensioned to fit into the slimmer forend of the A-5 which requires alot of machining and tapering of the Block. I wanted as much metal in the block as possible to retain rigidity and stiffness but was limited in what the final shape could be. The final result looks like it will be plenty stiff for extreme accuracy.

371979.jpg

This is the finished rifle ready for load development and range testing. Componants are a Rem 700 LA converted to single shot, fully accurized, Holland Comp recoil lug, Special Lilja Xtreme Sporter V-Block contour barrel, 30" fluted 1-8 3 groove. Holland QD brake, McMillan A-5 stock, Rifles Basix 1.5 lb trigger and APS V-Block.

371981.jpg


Finished rifle weight is roughly 13.5 lbs as she is seen in the pictures. Certainly not a lightweight sporter but if the system performs as it should, the rifle will produce consistancy far above what a conventional 13 lb rifle will produce.

371983.jpg


Performance wise, we are looking to break 3500 fps with the 169.5 gr ULD RBBT and hopefully get the new 185 gr ULD RBBT up to the 3300 fps range. If we can get this, the 277 AM will rival the 7mm AM/200 gr ULD RBBT combo ballistically.

As with all the Allen Magnums, these are Full throttle big game rifles, not varmint rifles so the shortened throat life is much less of a concern then a high volume shooter.

371984.jpg


This rifle was designed and built, along with the new round to reach out and hammer Canadian whitetails out to 1000 yards reliably in a portable rifle system. Hopefully it will do this easily.

All opinions welcome if you care to share your thoughts on this idea.

Good Shooting!!

Kirby Allen(50)
 
Kirby:

Fantastic /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/shocked.gif /ubbthreads/images/graemlins/smile.gif I've been waiting for this to show up and it looks like it all came together as planned.

I don't think Richard will be wanting for anything when he gets his hands on this. One thing for sure, this means the 277 cal guys will be getting their heavier bullets pretty quick. /ubbthreads/images/graemlins/smile.gif

I like the looks and had wondered what the final v-block design would look like. I like it. I'm really curious to see how the accuracy is with the new system and I have no doubts about it's capabilities to hammer a whitetail about as far as Richard can see one. Keep us posted with the range results.

Don't know if I'll show this to my buddy or not. He's shipping his 270 AM to you this week and he might be tempted to have it re-chambered but I think he'll more than likely wait until it's time for a new barrel.

At this weight limit for the gun do you think the accuracy and consistency of the gun will be equal to or greater than a conventionally bedded rifle?

From the chamber/block area forward, what is the barrel contour comparable to? #7, #8???

How heavy, and what length of a barrel would this system handle if utilized in a standard type stock such as the A-5?

Again, great looking gun and I congratulate Richard on his new gun and you on your continued work to make a better long range hammer and also in finding a new way to keep us broke /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/smile.gif /ubbthreads/images/graemlins/grin.gif
 
There you go again, posting pics and making want another rifle /ubbthreads/images/graemlins/mad.gif!

I have no doubt that those Canadian deer are in some serious trouble. Can't wait to see what she does w/those big 185 gr bullets!!!

Of course, I can't wait to see what wimpy little 270 AM will do w/them as well!!
 
[ QUOTE ]
'This rifle is the very first design of my Extreme Sporter V-Block rifle system... The idea was to take the design of the Heavy V-Block but modify it and streamline it to work in a rifle in the 10-12 range instead of 25 to 30 lbs for my Heavy V-Blocks. And doing this while still offering the extreme stability that the V-Block barrel bedding system offers as well.... As with the Heavy V-Block, the Xtreme Sporter V-Block has a totally free floated receiver. Nothing behind the recoil lug bares solidly on the stock in any way. The barrel is held solidly into the V-Block by two 1/4-28 bolts.'

[/ QUOTE ]

I did a search to see if anyone else has asked the question, but have not seen this asked before... you mentioned free-floating the receiver past the recoil lug? This doesn't cause any issues with the scope i.e shifting POI? I take it / assume that the v-block abosorbs the stress and energy from recoil, so a receiver doesn't have to be bedded in.... or that the recoil lug takes any of the residual stress for the receiver. Sorry, just a little curious... it looks way cool (as my son would say). The v-block, I gather from the previous posts, is for long, heavy barrels that you would not want to free float (and stress the action/receiver with, thus getting poor accuracy). Looks like a good concept and application!

I can see this in my gun safe in the next year or two... or better yet at the range instead of the safe! Can't wait to hear about accuracy out to 400-1000 yards, looks like it will be really neat.

Congrats to Richard!

EZ
 
WEll I talked to him the other day and we discussed who's would be ready first. LOL

I have to admit that it really turned out great. Not that I had any doubts.

I am sure that this rig should have no problems dumping a big whitetail with a properly stoked up 185 gr Wildcat.
 
[ QUOTE ]
Can't wait to hear about accuracy out to 400-1000 yards,

[/ QUOTE ]

I'm thinkin' 1000 out towards 2000. Should still have enough umph to do in a chuck or yote.....

Several questions though:

a)V-block "glued" into the stock?
b)Necessity of recoil lug? Safety or part of design?

and




Why are ss7mm's eyes buggin' out so far? Looks like they are even a little red from a restless night since Kirby posted those pics. /ubbthreads/images/graemlins/blush.gif
 
SS7mm,

We will see when the bullets hit the paper but things should work very well I suspect!

As to the 270 AM, I am currently not chambering the 277 or 7mm in the Savage rifles until I can chamber one and prove that it will handle the increased case diameter of the Lapua case.

I am sure it would as this rifle was chambered in the Lazzeroni Patriot and Tomahawk SA magnums which have the same head diameter but just want to prove it to myself first.

The contour on this barrel is roughly a #7 ahead of the 8" full diameter barrel shank. I am about to order another contour design from Dan which is basically the same thing but with a #5 contour to drop another pound off the barrel weight. This will happen after I test this design and prove it meets my goals for this design.

This V-Block design will handle up to a 1.250" straight cylinder barrel of at least 32" in length with this stock.

For a larger diameter 1.350" barrel up to 36" in length I recommend my 10" V-block system which is to large for this stock design.

Keep in mind that the A-5 would have to have some serious ballast in the butt stock to balance the rifle. This specific rifle balances about 1.5" ahead of the receiver face which in my opinion is pretty good considering the light weight of the stock and all the metal ahead of this point of the rifle.

Will let you know how she shoots.

Kirby Allen(50)
 
Bill,

The 277 was not developed in any way to make the 270 AM obsolete. It is much more involved to load the 277 AM because of the parent case.

For ease of loading and high performance, the 270 AM is still the best of the lot in my opinion. The 277 will outperform the 270 espeically with the 185 gr class bullets but they are both so far superior to the other 270s around that its not worth even comparing.

In fact you have to get into the huge 30 and 338 magnums to get the ballistic performance of either of these two rounds so you are not giving much up in performance.

Kirby Allen(50)
 
Looks **** nice Kirby,

I think I have seen that barrel contour before /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/laugh.gif, looks like a good rifle for a good guy

Like SS7mm said hopefully this means the big 185gr ULD is on its way, we are dang near dry on bullets down in OK.

Looks guide, i am ready to see how she drives


take it easy
steve
 
EZ Shooter,

Actually floating the receiver eliminates any issues with the receiver flexing under the weight of the barrel or during recoil.

The Rem 700 receivers are pretty stiff until you hang a heavy 30" barrel off it in a conventional bedding system. In the Barrel bedding V-Block system, all the receiver needs to do is support its own weight and that of the scope, basically nothing compared to what is asked of the receiver during conventional bedding.

The recoil energy is transferred to the stock in the same traditional manor as a conventionally bedded rifle using a recoil lug that contacts the stock. All the Barrel bedding V-Block does is provide an extremely consistant and stiff, support for the barrel.

Basically the barrel supports its own weight as well as the receiver and scope which it is more then strong enough to do.

The V-Block does not absorb any recoil energy in my design unlike the clamp on block designs. As such there has to be a recoil lug to transfer recoil energy to the stock. This may be a disadvantage to those using the clamp on block designs but there are also several advantages as well.

Mainly,

1. size of the stock can be dramatically slimmer
2. Rifle weight can be kept lower
3. Scope mounting height is conventional
4. Rifle retains traditional appearance

The basic idea behind my design and all the V-Block and barrel bedding block designs is this. This is an extreme example to show you the idea clearly.

Say you have a 1.250" straight cylinder barrel that is 35" long. If you fit this barrel and bed it conventionally to most receivers and full float the barrel you will have a VERY long unsupported barrel which may cause some accuracy issues with receiver flexing.

Now if you take this same barrel and use a 10" V-Block, now you still have the 35" 1.250" diameter barrel but only 25" of it are floated. The first 10" of the barrel are solidly held by the V-block.

Now anyone can easily see the advantages of this. Instead of having 35" of heavy unsupported barrel, now you have only 25" of heavy unsupported barrel.

Barrel stiffness is key to fine accuracy. Stable bedding is key to consistancy. Now a 25", 1.250" diameter barrel is EXTREMELY stiff and a 10" long heat treated aluminum V-Block is about as stable as it gets for bedding.

Basically you get all the advantages ballistically of a 35" barrel but with the rigidness and stability of a realatively short 25", 1.250" diameter barrel.

Floating the receiver really does not offer any significant accuracy advantages, what it does do though is eliminate the possibility for some very serious accuracy degrading issues.

Good Shooting!!

Kirby Allen(50)
 
Roy,

Yes this system will offer 2K potential I am quite confident. I have tested my heavy sporter in 270 AM out to 2200 yards and in good conditions it was consitantly grouping in the 1 moa range at this distance. Still, thats just shy of 2 foot groups but at that range I was happy.

This rifle will do better.

The V-Block is bedded permanently into the stock. If you look at the pics of the V-Block you will see the releif groove milled into the bottom and sides of the block. These are basically to increase the bond strength to the stock when bedded and all these grooves are filled with bedding compound. There are similiar but smaller cuts in the inside of the stock as well.

There has to be a recoil lug used with my design. The reason there is no lug used with the large clamp on block designs is because the block hsa enough clamping strength to securely hold the barrel under recoil and then the block itself is used for the purpose of a recoil lug.

My design is totally differnet.

While the barrel is solidly held down into the V-block via two 1/4-28 bolt that are threaded directly into the barrel, this is not a strong enough hold to eliminate the need for a recoil lug.

In fact, the two mounting bolts are totally floated in the V-Block and seat on 82 degree counter sinks. The only thing that contacts is the tapered head of the bolt against the bottom of the V-Block and the threads in the barrel.

As such, if there was no recoil lug, the recoil energy would easily be enough to shift the barreled receiver back in the V-Block until the bolts were binding agains the block. At which point, shearing of the bolts would probably be soon to come.

Using a conventional Recoil lug prevents this issue so using them together offers the advantages of the clamp on block design but in a package that is conventional in appearance and allows much slimmer rifles and conventional scope mounting heights.

Some will say threading the bolts directly in the barrel is a bad idea. I have yet to see any accuracy issues doing this if done properly.

Mr. Holland has been building rifles using a similiar design for many years with no problems. My design is similiar but totally unique in comparision to his design. Same ideas used for the design though.

If we get the ballistic numbers we are prediction, at 2000 yards, and the 185 gr ULD RBBT will still be climping along at nearly 1600 fps and packing just over 1000 ft/lbs of energy. Thats plenty for deer size game give a quality shot placement to the vitals.

Now I am not saying this is a 2000 yard deer rifle, just showing the numbers that we are hoping to get out of this rifle.

More realistic is 1000 yard deer hunting. At this point we will be looking at 2330 fps and +2200 ft/lbs of energy. Not to bad for a 270!!!

We will see what actually happens when the bullets get in the air though!!

Kirby Allen(50)
 
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